Clinical outcomes of minimally invasive endoscopic and conventional sternotomy approaches for atrial septal defect repair

Background

Concerns remain that minimally invasive atrial septal defect (ASD) repair may compromise patient outcomes. We compared clinical outcomes of adult patients undergoing ASD repair via a minimally invasive endoscopic approach versus a “gold standard” sternotomy.

Methods

We retrospectively reviewed the clinical outcomes of consecutive patients who underwent ASD patch repair at our institution between 2002 and 2012. We compared in-hospital/30-day mortality, postoperative complications, length of stay in hospital and in the intensive care unit and blood product requirements between patients who underwent right mini-thoracotomy (MT) and those who underwent conventional sternotomy.

Results

During the study period, 73 consecutive patients underwent ASD patch repair at our institution: 51 (age 47 ± 16 yr, 66.7% women) in the MT group and 22 (age 46 ± 21 yr, 59.1% women) in the sternotomy group. In-hospital mortality was similar between the 2 groups (MT 0% v. sternotomy 4.5%, p = 0.30). There were no significant differences in any postoperative complications or blood product requirements. No patients in the MT group suffered stroke, retrograde aortic dissection or leg ischemia. Mean intensive care unit (MT 1.2 ± 1.2 d v. sternotomy 1.7 ± 2.2 d, p = 0.26) and hospital length of stays (MT 5.1 ± 2.2 d v. sternotomy 6.3 ± 3.6 d, p = 0.17) were similar between the groups; however, there was a trend toward fewer patients requiring prolonged hospital stays (> 10 d) in the MT group (3.9% v. 18.2%, p = 0.06).

Conclusion

Repair of ostium secundum and sinus venosus ASD can be performed safely via MT endoscopic approach with similar outcomes as sternotomy. Patient preference for a more cosmetically appealing incision may be considered without concern of compromised outcomes.     

Functional outcomes and cost estimation for extra-articular and simple intra-articular distal radius fractures treated with open reduction and internal fixation versus closed reduction and percutaneous Kirschner wire fixation

Background

We sought to compare direct costs and clinical and radiographic outcomes for distal radius fractures (DRF) treated with open reduction internal fixation with volar locking plates (VLP) versus closed reduction and percutaneous pinning (CRPP).

Methods

We identified patients with AO-type A and C1 DRFs from a prospective database. Outcomes were assessed at 6 weeks and at 3, 6 and 12 months, and surgical care costs were estimated.

Results

Twenty patients were treated with CRPP and 24 with VLP. There were no significant differences in patient-rated wrist evaluation (PRWE) scores between the 2 groups at any time point (mean 16.2 ± 23.1 in the CRPP group v. 21.5 ± 23.6 in the VLP group, p = 0.91). Overall alignment was maintained in both groups; however, there was a greater loss of radial height over time with CRPP than VLP (0.97 mm v. 0.25 mm, p = 0.018). The mean duration of surgery was longer for VLP than CRPP (113.9 ± 39.5 min v. 86.5 ± 7.8 min, p = 0.029), but there were fewer clinic visits (5.2 ± 1.4 v. 7.8 ± 1.3, p < 0.001) and fewer radiographs (7.4 ± 2.7 v. 9 ± 2.4, p = 0.031). The total cost per case was greater for VLP than CRPP ($1637.27 v. $733.91).

Conclusion

Based on PRWE scores, VLPs did not offer any significant advantage over CRPP in patients with simple fracture types between 3 and 12 months, but they were much more costly. Whether VLP offers any functional advantage earlier in recovery, thereby justifying their expense, requires further investigation in the form of a prospective randomized trial with a detailed cost analysis.     

Results of Revision Surgery and Causes of Unstable Total Knee Arthroplasty

Background

The aim of this study was to evaluate causes of unstable total knee arthroplasty and results of revision surgery.

Methods

We retrospectively reviewed 24 knees that underwent a revision arthroplasty for unstable total knee arthroplasty. The average follow-up period was 33.8 months. We classified the instability and analyzed the treatment results according to its cause. Stress radiographs, postoperative component position, and joint level were measured. Clinical outcomes were assessed using the Hospital for Special Surgery (HSS) score and range of motion.

Results

Causes of instability included coronal instability with posteromedial polyethylene wear and lateral laxity in 13 knees, coronal instability with posteromedial polyethylene wear in 6 knees and coronal and sagittal instability in 3 knees including post breakage in 1 knee, global instability in 1 knee and flexion instability in 1 knee. Mean preoperative/postoperative varus and valgus angles were 5.8°/3.2° (p = 0.713) and 22.5°/5.6° (p = 0.032). Mean postoperative α, β, γ, δ angle were 5.34°, 89.65°, 2.74°, 6.77°. Mean changes of joint levels were from 14.1 mm to 13.6 mm from fibular head (p = 0.82). The mean HSS score improved from 53.4 to 89.2 (p = 0.04). The average range of motion was changed from 123° to 122° (p = 0.82).

Conclusions

Revision total knee arthroplasty with or without a more constrained prosthesis will be a definite solution for an unstable total knee arthroplasty. The solution according to cause is very important and seems to be helpful to avoid unnecessary over-constrained implant selection in revision surgery for total knee instability.     

Medial Patellofemoral Ligament Reconstruction for Recurrent Patellar Instability Using a Gracilis Autograft without Bone Tunnel

Background

Several tendon graft and fixation methods have been introduced in medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar dislocation. The purpose of this study was to evaluate the results of MPFL reconstruction using a gracilis autograft fixation without bone tunnel in patients with recurrent patellar instability.

Methods

Nine patients (four males and five females) diagnosed with recurrent patellar instability from July 2009 to January 2013 and had MPFL reconstruction using a gracilis autograft were included. The average age of the patients was 24.6 years (range, 13 to 48 years), and the average follow-up period was 19.3 months (range, 12 to 30 months). For every patient, femoral attachment was fixed using suture anchors securing the patella by suturing the periosteum and surrounding soft tissue. Clinical evaluation included the Kujala, Lysholm, and Tegner scores; in addition, patients were examined for any complication including recurrent dislocation. The congruence angle and patella alta were assessed radiologically before and after surgery.

Results

The Kujala score improved from an average of 42.7 ± 8.4 before surgery to 79.6 ± 13.6 (p = 0.008) at final follow-up; the Lysholm score improved from 45.8 ± 5.7 to 82.0 ± 10.5 (p = 0.008); and the Tegner score improved from 2.8 ± 0.8 to 5.6 ± 1.5 (p = 0.007). The Insall-Salvati ratio changed from 1.16 ± 0.1 (range, 0.94 to 1.35) before surgery to 1.14 ± 0.1 (range, 0.96 to 1.29; p = 0.233) at the final follow-up without significance. The congruence angle significantly improved from 26.5° ± 10.6° (range, 12° to 43°) before surgery to -4.0° ± 4.3° (range, -12° to 5°; p = 0.008) at final follow-up. Subluxation was observed in one patient and hemarthrosis occurred in another patient 2 years after surgery, but these patients were asymptomatic.

Conclusions

We achieved good results with a patellar fixation technique in MPFL reconstruction using a gracilis autograft employing soft tissue suturing in patients with recurrent patellar dislocation.     

Spinal deformity progression after posterior segmental instrumentation and fusion for idiopathic scoliosis

Study design

Retrospective chart and radiographic review.

Purpose

To assess the incidence of and variables associated with spinal deformity progression after posterior segmental instrumentation and fusion at a single institution. Progression of the scoliotic deformity after posterior instrumented spinal fusion has been described. Recent studies have concluded that segmental pedicle screw constructs are better able to control deformity progression.

Methods

Retrospective review of a consecutive series of idiopathic scoliosis patients (n = 89) with major thoracic curves (Lenke types 1–4) treated with posterior segmental instrumentation and fusion. Deformity progression was defined as a 10° increase in Cobb angle between the first-erect and 2-year post-operative radiographs. Clinical and radiographic data between the two cohorts (deformity progression versus stable) were analyzed to determine the variables associated with deformity progression.

Results

Patients in the deformity progression group (n = 13) tended to be younger (median 13.7 vs. 14.7 years) and experienced a significant change in height (p = 0.01) during the post-operative period compared to the stable group (n = 76). At 2-years post-op, the patients in the deformity progression group had experienced a significantly greater change in upper instrumented vertebra (UIV) angulation, lower instrumented vertebra (LIV) angulation, and apical vertebral translation (AVT). Two-year post-op Scoliosis Research Society questionnaire (SRS-22) scores in the appearance domain were also significantly worse in the deformity progression group. Patients in the deformity progression group had a significantly greater difference between the lowest instrumented vertebra and stable vertebra compared to patients in the stable group (p = 0.001).

Conclusions

Deformity progression after posterior spinal fusion does occur after modern segmental instrumentation. Segmental pedicle screw constructs do not prevent deformity progression. Skeletally immature patients with a significant growth potential are at the highest risk for deformity progression. In immature patients, extending the fusion distally to the stable vertebra may minimize deformity progression.

Level of evidence

Level III.     

Clinical outcomes compared between laparoscopic and open appendectomy in pregnant women

Background

Despite the initial absolute or relative contraindication of laparoscopic surgery during pregnancy, in the last decade, laparoscopic appendectomy (LA) has been performed in pregnant women. But few studies compare the outcomes of LA compared with open appendectomy (OA). We investigated clinical outcomes to evaluate the safety and efficacy of LA compared with OA in pregnant women.

Methods

We recruited consecutive pregnant patients with a diagnosis of acute appendicitis who were undergoing LA or OA between May 2007 and August 2011 into the study.

Results

Sixty-one patients (22 LA and 39 OA) enrolled in our study. There were no significant differences in duration of surgery, postoperative complication rate and obstetric and fetal outcomes, including incidence of preterm labour, delivery type, gestation age at delivery, birth weight and APGAR scores between the 2 groups. However, the LA group had shorter time to first flatus (2.4 ± 0.4 d v. 4.0 ± 1.7 d, p = 0.034), earlier time to oral intake (2.3 ± 1.6 d v. 4.1 ± 1.9 d, p = 0.023) and shorter postoperative hospital stay (4.2 ± 2.9 d v. 6.9 ± 3.7 d, p = 0.043) than the OA group.

Conclusion

Laparoscopic appendectomy is a clinically safe and effective procedure in all trimesters of pregnancy and should be considered as a standard treatment alternative to OA. Further evaluation including prospective randomized clinical trials comparing LA with OA are needed to confirm our results.     

Usefulness of Arthroscopic Treatment of Painful Hip after Acetabular Fracture or Hip Dislocation

Background

Painful hip following hip dislocation or acetabular fracture can be an important signal for early degeneration and progression to osteoarthritis due to intraarticular pathology. However, there is limited literature discussing the use of arthroscopy for the treatment of painful hip. The purpose of this retrospective study was to analyze the effectiveness and benefit of arthroscopic treatment for patients with a painful hip after major trauma.

Methods

From July 2003 to February 2013, we reviewed 13 patients who underwent arthroscopic treatment after acetabular fracture or hip dislocation and were followed up for a minimum of 2 postoperative years. The degree of osteoarthritis based on the Tonnis classification pre- and postoperatively at final follow-up was determined. Clinical outcomes were evaluated using visual analogue scale for pain (VAS) and modified Harris hip score (MHHS), and range of motion (ROM) of the hip pre- and postoperatively at final follow-up.

Results

There were nine male and four female patients with a mean age at surgery of 28 years (range, 20 to 50 years). The mean follow-up period of the patients was 59.8 months (range, 24 to 115 months), and the mean interval between initial trauma and arthroscopic treatment was 40.8 months (range, 1 to 144 months). At the final follow-up, VAS and MHHS improved significantly from 6.3 and 53.4 to 3.0 and 88.3, respectively (p = 0.002 and p < 0.001, respectively). However, there were no significant differences in hip flexion, abduction, adduction, external rotation, and internal rotation as minor improvements from 113.1°, 38.5°, 28.5°, 36.5°, and 22.7° to 118.5°, 39.0°, 29.2°, 38.9°, and 26.5° were observed, respectively (p = 0.070, p = 0.414, p = 0.317, p = 0.084, and p = 0.136, respectively). None of the patients exhibited progression of osteoarthritis of the hip at the final follow-up.

Conclusions

Arthroscopic treatment after acetabular fracture or hip dislocation is effective and delays the progression of traumatic osteoarthritis.     

Volume and Contact Surface Area Analysis of Bony Tunnels in Single and Double Bundle Anterior Cruciate Ligament Reconstruction Using Autograft Tendons: In Vivo Three-Dimensional Imaging Analysis

Background

Regarding reconstruction surgery of the anterior cruciate ligament (ACL), there is still a debate whether to perform a single bundle (SB) or double bundle (DB) reconstruction. The purpose of this study was to analyze and compare the volume and surface area of femoral and tibial tunnels during transtibial SB versus transportal DB ACL reconstruction.

Methods

A consecutive series of 26 patients who underwent trantibial SB ACL reconstruction and 27 patients with transportal DB ACL reconstruction using hamstring autograft from January 2010 to October 2010 were included in this study. Three-dimensional computed tomography (3D-CT) was taken within one week after operation. The CT bone images were segmented with use of Mimics software v14.0. The obtained digital images were then imported in the commercial package Geomagic Studio v10.0 and SketchUp Pro v8.0 for processing. The femoral and tibial tunnel lengths, diameters, volumes and surface areas were evaluated. A comparison between the two groups was performed using the independent-samples t-test. A p-value less than the significance value of 5% (p < 0.05) was considered statistically significant.

Results

Regarding femur tunnels, a significant difference was not found between the tunnel volume for SB technique (1,496.51 ± 396.72 mm³) and the total tunnel volume for DB technique (1,593.81 ± 469.42 mm³; p = 0.366). However, the total surface area for femoral tunnels was larger in DB technique (919.65 ± 201.79 mm²) compared to SB technique (810.02 ± 117.98 mm²; p = 0.004). For tibia tunnels, there was a significant difference between tunnel volume for the SB technique (2,070.43 ± 565.07 mm³) and the total tunnel volume for the DB technique (2,681.93 ± 668.09 mm³; p ≤ 0.001). The tibial tunnel surface area for the SB technique (958.84 ± 147.50 mm²) was smaller than the total tunnel surface area for the DB technique (1,493.31 ± 220.79 mm²; p ≤ 0.001).

Conclusions

Although the total femoral tunnel volume was similar between two techniques, the total surface area was larger in the DB technique. For the tibia, both total tunnel volume and the surface area were larger in DB technique.     

The lifetime risk of pneumonia in patients with neuromuscular scoliosis at a mean age of 21?years: the role of spinal deformity surgery

Background

Patients with neuromuscular disorders often have an increased risk of pneumonia and decreased lung function, which may further be compromised by scoliosis. Scoliosis surgery may improve pulmonary function in otherwise healthy patients, but no study has evaluated its effect on the risk of pneumonia in patients with neuromuscular scoliosis (NMS).

Methods

The patient charts of 42 patients (mean age 14.6 years) who had undergone surgery for severe NMS (mean scoliosis 86°) were retrospectively reviewed from birth to a mean of 6.1 years (range 2.8–9.5) after scoliosis surgery. The main outcome was radiographically confirmed pneumonia as a primary cause for hospitalization. We excluded postoperative (3 months) pneumonia from the analyses.

Results

The lifetime annual incidence of pneumonia was 8.0/100 before and 13.4/100 after scoliosis surgery (p > 0.10). The mean number of hospital days per year due to pneumonia were 0.59 (SD 2.3) before scoliosis surgery and 2.24 (SD 6.9) after surgery (p > 0.10). Multivariate analysis demonstrated that lifetime risk factors for pneumonia were epilepsy (RR 15.2, 95 % CI 1.3–176.8, p = 0.027), non-cerebral palsy (CP) etiology (RR = 10.2, 95 % CI 3.2–32.7, p < 0.001) and major scoliosis (main curve >70°; RR = 11.3, 95 % CI 1.8–70.7, p = 0.01).

Conclusions

Epilepsy, non-CP etiology and major scoliosis are significant risk factors for pneumonia in patients with NMS. Scoliosis surgery does not decrease the incidence of pneumonia in patients with severe NMS.

Level of Evidence

Retrospective comparative study, Level III.

Electronic supplementary material

The online version of this article (doi:10.1007/s11832-015-0682-8) contains supplementary material, which is available to authorized users.     

Lumbar Lordosis of Spinal Stenosis Patients during Intraoperative Prone Positioning

Background

To evaluate the effect of spondylolisthesis on lumbar lordosis on the OSI (Jackson; Orthopaedic Systems Inc.) frame. Restoration of lumbar lordosis is important for maintaining sagittal balance. Physiologic lumbar lordosis has to be gained by intraoperative prone positioning with a hip extension and posterior instrumentation technique. There are some debates about changing lumbar lordosis on the OSI frame after an intraoperative prone position. We evaluated the effect of spondylolisthesis on lumbar lordosis after an intraoperative prone position.

Methods

Sixty-seven patients, who underwent spinal fusion at the Department of Orthopaedic Surgery of Gwangmyeong Sungae Hospital between May 2007 and February 2012, were included in this study. The study compared lumbar lordosis on preoperative upright, intraoperative prone and postoperative upright lateral X-rays between the simple stenosis (SS) group and spondylolisthesis group. The average age of patients was 67.86 years old. The average preoperative lordosis was 43.5° (± 14.9°), average intraoperative lordosis was 48.8° (± 13.2°), average postoperative lordosis was 46.5° (± 16.1°) and the average change on the frame was 5.3° (± 10.6°).

Results

Among all patients, 24 patients were diagnosed with simple spinal stenosis, 43 patients with spondylolisthesis (29 degenerative spondylolisthesis and 14 isthmic spondylolisthesis). Between the SS group and spondylolisthesis group, preoperative lordosis, intraoperative lordosis and postoperative lordosis were significantly larger in the spondylolisthesis group. The ratio of patients with increased lordosis on the OSI frame compared to preoperative lordosis was significantly higher in the spondylolisthesis group. The risk of increased lordosis on frame was significantly higher in the spondylolisthesis group (odds ratio, 3.325; 95% confidence interval, 1.101 to 10.039; p = 0.033).

Conclusions

Intraoperative lumbar lordosis on the OSI frame with a prone position was larger in the SS patients than the spondylolisthesis patients, which also produced a larger postoperative lordosis angle after posterior spinal fusion surgery. An increase in lumbar lordosis on the OSI frame should be considered during posterior spinal fusion surgery, especially in spondylolisthesis patients.     

Presentation of frozen shoulder among diabetic and non-diabetic patients

Objective

The literature is inconsistent regarding the level of pain and disability in frozen shoulder patients with or without diabetes mellitus. The aim of this study is to evaluate some demographic features of frozen shoulder patients and to look into the disparity of information by comparing the level of pain and disability due to frozen shoulder between diabetic and non-diabetic people.

Design

This is a prospective comparative study. People with frozen shoulder attending an outpatient department were selected by consecutive sampling. Disability levels were assessed by the Shoulder Pain & Disability Index (SPADI). Means of pain and disability scores were compared using unpaired t-test.

Results

Among 140 persons with shoulder pain 99 (71.4%) had frozen shoulder. From the participating 40 frozen shoulder patients, 26 (65%) were males and 14 (35%) were females. Seventeen participants (42.5%) were diabetic, two (5%) had impaired glucose tolerance and 21 (52.5%) patients were non-diabetic. Mean disability scores (SPADI) were 51 ± 15.5 in diabetic and 57 ± 16 in non-diabetic persons. The differences in pain and disability level were not statistically significance (respectively, p = 0.24 and p = 0.13 at 95% confidence interval).

Conclusions

No difference was found in level of pain and disability level between frozen shoulder patients with and without diabetes.     

Caput valgum associated with developmental dysplasia of the hip: management by transphyseal screw fixation

Purpose

A late finding of some hips treated for developmental dysplasia of the hip (DDH) is a growth disturbance of the lateral proximal femoral physis, which results in caput valgum and possibly osteoarthritis. Current treatment options include complete epiphysiodesis of the proximal femoral physis or a corrective proximal femoral osteotomy. Alternatively, a transphyseal screw through the inferomedial proximal femoral physis that preserves superolateral growth might improve this deformity.

Methods

This study evaluates the effect of such a transphyseal screw on both femoral and acetabular development in patients with caput valgum following open treatment of DDH. These patients were followed clinically and radiographically until skeletal maturity. Preoperative and postoperative radiographs were assessed, measuring the proximal femoral physeal orientation (PFPO), the head–shaft angle (HSA), Sharp’s angle and the center edge angle of Wiberg (CE angle).

Results

Thirteen hips of 11 consecutive patients were followed prospectively. The age at the time of transphyseal screw placement was between 5 and 14 years. The mean improvement of the PFPO and HSA was 14° (p < 0.01) and 11° (p < 0.001), respectively. The mean improvement of Sharp’s angle and CE angle was 4.7° (p < 0.01) and 5.8° (p < 0.02), respectively. Five patients underwent screw revision.

Conclusions

A transphyseal screw across the proximal femoral physis improved the proximal femur and acetabular geometry.     

Comparison of the major intraoperative and postoperative complications between unilateral and sequential bilateral total knee arthroplasty in a high-volume community hospital

Background

Total knee arthroplasty (TKA) is a common surgical treatment for arthritis. In the event of bilateral knee symptoms, a patient may elect for bilateral TKA (BTKA) under 1 anesthetic or 2 separate unilateral TKAs (UTKA). Controversy exists in the literature regarding the safety of BTKA versus UTKA. We compared the rate of major intraoperative and postoperative complications for BTKA versus UTKA at a high-volume community hospital.

Methods

We compared 373 patients who underwent BTKA with 966 who underwent UTKA between May 2008 and May 2011. Health records were used to determine patient characteristics and major intraoperative and postoperative complications. The BTKA and UTKA cohorts were matched for demographic characteristics and comorbidities with the exception of previous transient ischemic attack and previous knee surgery (UTKA > BTKA).

Results

Rates of intraoperative and postoperative complications, including cardiovascular, thromboembolic and neurologic complications; deep wound infections; and mortality, did not differ significantly between groups. Bilateral TKA was associated with a greater proportion of patients requiring blood transfusion than UTKA (29.8% v. 8.9%, p < 0.001). Among those transfused, there was no significant difference between the groups in the mean number of units required (1.72 ± 0.77 v. 1.53 ± 0.85 units, p = 0.68).

Conclusion

Bilateral TKA was not associated with statistically greater rates of intra-operative and postoperative complications than UTKA, barring the proportion of patients requiring transfusion. Our results support the use of BTKA to treat bilateral knee arthritis in a high-volume community hospital setting.     

Associations between radiographic characteristics and change in renal function following partial nephrectomy using 24-hour creatinine clearance

Background

Radiographic characteristics may be associated with the degree of renal function preservation following partial nephrectomy. The purpose of this study was to determine the impact of preoperative radiographic variables on change in renal function using 24-hour urine creatinine clearance (uCrCl).

Methods

Patients with partial nephrectomy performed from November 2003 to 2008 were enrolled in the study. Serum creatinine and 24-hour urine was collected preoperatively and at 3, 6 and 12 months postoperatively. Computed tomography or magnetic resonance imaging was used to determine tumour size, tumour location and renal volume.

Results

Of the 36 patients, median age was 62 (range 30–78) and 21 (58%) were male. The mean tumour diameter was 2.8±1.4 cm. Twenty-two (61%) tumours were located at the renal pole and 11 (31%) were endophytic. Overall, mean preoperative uCrCl was 88.8±34.2 mL/min and mean postoperative uCrCl was 82.8±33.6 mL/min (6.8%; p < 0.01). On multivariable analysis, no single characteristic was associated with a clinically prohibitive decrease in renal function (−9.4% if endophitic, p = 0.06; −0.57% per cm diameter, p = 0.73; and −6.9% if located at the renal pole, p = 0.15). The total renal volume was also not significantly associated with renal function change (−1.1% per 100 cc, p = 0.86).     

Usefulness of Prone Cross-Table Lateral Radiographs in Vertebral Compression Fractures

Background

Dynamic radiographs are recommended to investigate non-healing evidence such as the dynamic mobility or intravertebral clefts in osteoporotic vertebral compression fractures (VCFs). However, it is difficult to examine standing flexion and extension lateral radiographs due to severe pain. The use of prone cross-table lateral radiographs (PrLRs) as a diagnostic tool has never been proposed to our knowledge. The purpose of this study is to clarify the usefulness of PrLRs in diagnosis and treatment of VCFs.

Methods

We reviewed 62 VCF patients examined with PrLRs between January 1, 2008 and June 30, 2011. To compare the degree of pain provoked between standing extension lateral radiographs (StLRs) and PrLRs, numeric rating scale (NRS) scores were assessed and compared by a paired t-test. Vertebroplasty was done for 40 patients and kyphoplasty was done for 9 patients with routine manners. To assess the degree of postural reduction, vertebral wedge angles (VWA) and vertebral height ratios (VHR) were calculated by using preoperative StLRs, PrLRs, and postoperative lateral radiographs. Two variables derived from changes in VWA and VHR between preoperative and postoperative radiographs were compared by a paired t-test.

Results

The average NRS scores were 6.23 ± 1.67 in StLRs and 5.18 ± 1.47 in PrLRs. The degree of pain provocation was lower in using PrLRs than StLRs (p < 0.001). The average changes of VWA between preoperative and postoperative status were 5.24° ± 6.16° with PrLRs and 3.46° ± 3.47° with StLRs. The average changes of VHR were 0.248 ± 0.178 with PrLRs and 0.148 ± 0.161 with StLRs. The comparisons by two variables showed significant differences for both parameters (p = 0.021 and p < 0.001, respectively). The postoperative radiological status was reflected more precisely when using PrLRs than StLRs.

Conclusions

In comparison with StLR, the PrLR was more accurate in predicting the degree of restoration of postoperative vertebral heights and wedge angles, and provoked less pain during examination. The PrLR could be a useful diagnostic tool to detect intravertebral cleft or intravertebral dynamic instability.     

Reduction in Bone Volume Resection with a Newer Posterior Stabilized Total Knee Arthroplasty Design

Background

Posterior stabilized total knee arthroplasty requires an intercondylar notch to accommodate the cam housing that articulates with the tibial post to create femoral rollback required for deep flexion. The volume of bone resected for the intercondylar notch varies with implant design, and newer designs may accommodate high flexion with less bone resection.

Questions/Purposes

This study aims to analyze the bone volume and density resected from the intercondylar notch for three posterior stabilized implants from a single company: a Posterior Stabilized (PS) system, a Hi-Flex system (HF), and a rounded new box-reamer (RB) system and to further assess whether the newer RB with a cylindrical cutting tool would preserve more native bone.

Materials and Methods

Using a computer model, the PS, HF, and RB femoral components were digitally implanted into CT scans of 19 cadaver femurs. Nine cadavers were fit with a size 4 implant, six with size 3, and four with a size 2. The volume of intercondylar bone resected digitally for femoral preparation was measured. Bone density was measured by CT scans in Hounsfield units (HU). A paired t test was used to compare the mean volume of bone resected for each implant.

Results

For the size 4 femurs, the newer RB design removed 8% less intercondylar bone than the PS design (7,832 ± 501 vs. 8,547 ± 377 mm³, p < 0.001) and 28% less bone than the HF design (7,832 ± 501 vs. 10,897 ± 444 mm³, p < 0.001). The average HU for size 4 femurs for RB design was 427 ± 72 (PS = 399 ± 69, p < 0.001; HF = 379 ± 66, p < 0.001). For the size 3 femurs, the RB design removed 12% less intercondylar bone than the PS (6,664 ± 786 vs. 7,516 ± 648 mm³, p < 0.001) and 27% less bone than the HF (6,664 ± 786 vs. 9,078 ± 713 mm³, p < 0.001). HU for size 3 femurs for the RB design was 452 ± 70 (PS = 422 ± 53, p < 0.1; HF = 410 ± 59, p < 0.01). For the size 2 femurs, the RB design removed 5% less intercondylar bone than the PS (5,730 ± 552 vs. 6,009 ± 472 mm³, p < 0.01) and 22% less bone than the HF (5,730 ± 552 vs. 7,380 ± 532 mm³, p < 0.001). HU for size 2 femurs for the RB design was 430 ± 48 (PS = 408 ± 55, p < 0.01; HF = 385 ± 56, p < 0.01).

Conclusions

The newer RB design removes less bone from the intercondylar notch than the classic PS and HF designs in all sizes tested. The bone-conserving cuts incorporated into this newer implant design appear to preserve native bone without compromising design objectives.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-013-9340-1) contains supplementary material, which is available to authorized users.     

Results of Corrective Osteotomy and Treatment Strategy for Ankylosing Spondylitis with Kyphotic Deformity

Background

To report the radiological and clinical results after corrective osteotomy in ankylosing spondylitis patients. Furthermore, this study intended to classify the types of deformity and to suggest appropriate surgical treatment options.

Methods

We retrospectively analyzed ankylosing spondylitis patients who underwent corrective osteotomy between 1996 and 2009. The radiographic assessments included the sagittal vertical axis (SVA), spinopelvic alignment parameters, correction angle, correction loss, type of deformity related to the location of the apex, and the craniocervical range of motion (CCROM). The clinical outcomes were assessed by the Oswestry Disability Index (ODI) scores.

Results

A total of 292 corrective osteotomies were performed in 248 patients with a mean follow-up of 40.1 months (range, 24 to 78 months). There were 183 cases of single pedicle subtraction osteotomy (PSO), 19 cases of multiple Smith-Petersen osteotomy (SPO), 17 cases of PSO + SPO, 14 cases of single SPO, six cases of posterior vertebral column resection (PVCR), five cases of PSO + partial pedicle subtraction osteotomy (PPSO), and four cases of PPSO. The mean correction angles were 31.9° ± 11.7° with PSO, 14.3° ± 8.4° with SPO, 38.3° ± 12.7° with PVCR, and 19.3° ± 7.1° with PPSO. The thoracolumbar type was the most common. The outcome analysis showed a significant improvement in the ODI score (p < 0.05). Statistical analysis revealed that the ODI score improvements correlated significantly with the postoperative SVA and CCROM (p < 0.05). There was no correlation between the clinical outcomes and spinopelvic parameters. There were 38 surgery-related complications in 25 patients (10.1%).

Conclusions

Corrective osteotomy is an effective method for treating a fixed kyphotic deformity occurring in ankylosing spondylitis, resulting in satisfactory outcomes with acceptable complications. The CCROM and postoperative SVA were important factors in determining the outcome.     

Novel Antibiotic-loaded Point-of-care Implant Coating Inhibits Biofilm

Background

Orthopaedic biomaterials are susceptible to biofilm formation. A novel lipid-based material has been developed that may be loaded with antibiotics and applied as an implant coating at point of care. However, this material has not been evaluated for antibiotic elution, biofilm inhibition, or in vivo efficacy.

Questions/purposes

(1) Do antibiotic-loaded coatings inhibit biofilm formation? (2) Is the coating effective in preventing biofilm in vivo?

Methods

Purified phosphatidylcholine was mixed with 25% amikacin or vancomycin or a combination of 12.5% of both. A 7-day elution study for coated titanium and stainless steel coupons was followed by turbidity and zone of inhibition assays against Staphylococcus aureus and Pseudomonas aeruginosa. Coupons were inoculated with bacteria and incubated 24 hours (N = 4 for each test group). Microscopic images of biofilm were obtained. After washing and vortexing, attached bacteria were counted. A mouse biofilm model was modified to include coated and uncoated stainless steel wires inserted into the lumens of catheters inoculated with a mixture of S aureus or P aeruginosa. Colony-forming unit counts (N = 10) and scanning electron microscopy imaging of implants were used to determine antimicrobial activity.

Results

Active antibiotics with colony inhibition effects were eluted for up to 6 days. Antibiotic-loaded coatings inhibited biofilm formation on in vitro coupons (log-fold reductions of 4.3 ± 0.4 in S aureus and 3.1 ± 0 for P aeruginosa in phosphatidylcholine-only coatings, 5.6 ± 0 for S aureus and 3.1 ± 0 for P aeruginosa for combination-loaded coatings, 5.5 ± 0.3 for S aureus in vancomycin-loaded coatings, and 3.1 ± 0 for P aeruginosa for amikacin-loaded coatings (p < 0.001 for all comparisons of antibiotic-loaded coatings against uncoated controls for both bacterial strains, p < 0.001 for comparison of antibiotic-loaded coatings against phosphatidylcholine only for S aureus, p = 0.54 for comparison of vancomycin versus combination coating in S aureus, P = 0.99 for comparison of antibiotic- and unloaded phosphatidylcholine coatings in P aeruginosa). Similarly, antibiotic-loaded coatings reduced attachment of bacteria to wires in vivo (log-fold reduction of 2.54 ± 0; p < 0.001 for S aureus and 0.83 ± 0.3; p = 0.112 for P aeruginosa).

Conclusions

Coatings deliver active antibiotics locally to inhibit biofilm formation and bacterial growth in vivo. Future evaluations will include orthopaedic preclinical models to confirm therapeutic efficacy.

Clinical Relevance

Clinical applications of local drug delivery coating could reduce the rate of implant-associated infections.     

Functional outcome of supracondylar elbow fractures in children: a 3- to 5-year follow-up

Background

Long-term functional outcomes of supracondylar elbow fractures (SCEF) have not been well documented in the literature. We retrospectively evaluated functional outcomes of pediatric SCEF using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire.

Methods

We retrospectively reviewed the outcomes of patients who presented to our tertiary care pediatric emergency department with SCEF between January 2005 and December 2009. We reviewed their charts to assess several clinical parameters, including age, sex, Gartland classification of SCEF, weight, comorbidities, treatment intervention, physiotherapy and the extremity involved. The DASH questionnaire was administered in 2012. We performed a multiple linear regression analysis to determine the significance of these clinical parameters as they related to the DASH score for functional outcome.

Results

We included 94 patients with SCEF in our review. Pediatric SCEF had good functional outcomes based on the DASH questionnaire (mean score 0.77 ± 2.10). We obtained the following DASH scores: 0.45 ± 2.20 for type I, 1.09 ± 1.70 for type II and 1.43 ± 2.40 for type III fractures. There was no statistical difference in functional outcome, regardless of sex (p = 0.07), age at injury (p = 0.96), fracture type (p = 0.14), weight (p = 0.59), right/left extremity (p = 0.26) or surgery (p = 0.52).

Conclusion

Our results demonstrate that good functional outcomes can be expected with pediatric SCEF based on the DASH questionnaire, regardless of age at injury, sex, weight, right/left extremity or surgical/nonsurgical intervention, provided satisfactory reduction is achieved and maintained.