How often is functional range of motion obtained by manipulation for stiff total knee arthroplasty?

Purpose

To evaluate how often manipulation under anesthesia (MUA) can achieve functional flexion ≥ 90 degrees and identify predictor for successful outcome of MUA for stiff total knee arthroplasty (TKA).

Methods

Demographic data, range of motion, and surgical and anesthetic information of 143 MUAs were retrospectively analyzed from 2000 to 2011.

Results

One-hundred thirty-six out of 143 patients (95 %) improved mean range of motion (ROM) from pre-MUA 62 ± 17° to final ROM 101 ± 21° (p < 0.001). Flexion ≥ 90 degrees was achieved in 74% (106/143) of patients. Regional anesthesia was identified as predictor of successful MUA outcome (p = 0.007, OR: 8.5, 95 % CI: 1.2-66.7).

Conclusions

Although the proportion of patients regaining flexion ≥ 90 degrees following MUA was less than those patients with simple overall ROM increase, the functional flexion ≥ 90 degrees was achieved in the vast majority of patients with stiff TKA following MUA.     

Reliability of radiographic measurements of knee motion following knee arthroplasty for use in a virtual knee clinic

INTRODUCTION

We sought to validate radiographic measurements of range of motion of the knee after arthroplasty as part of a new system of virtual clinics.

METHODS

The range of motion of 52 knees in 45 patients was obtained by 2 clinicians using standardised techniques and goniometers. Inter-rater reliability and intraclass correlation coefficients (ICCs) were calculated. Radiographs of these patients’ knees in full active flexion and extension were also used to calculate intra and inter-rater reliability compared with clinical measurements using four different methods for plotting angles on the radiographs.

RESULTS

The ICC for inter-rater reliability using the goniometer was very high. The ICC was 0.91 in extension and 0.85 in flexion while repeatability was 8.49° (-8.03–8.99°) in extension and 5.23° (-4.54–5.74°) in flexion. The best ICC for radiographic measurement in extension was 0.86, indicating ‘near perfect’ agreement, and repeatability was 5.43° (-4.04–6.12°). The best ICC in flexion was 0.95 and repeatability was 5.82° (-3.38–6.55°). The ICC for intrarater reliability was 0.98 for extension and 0.99 for flexion on radiographic measurements.

CONCLUSIONS

Validating the use of radiographs to reliably measure range of motion following knee arthroplasty has allowed us to set up a ‘virtual knee clinic’. Combining validated questionnaires and radiographic measurement of range of motion, we aim to maintain high quality patient surveillance following knee arthroplasty, reduce our ratio for new to follow-up patients in line with Department of Health guidelines and improve patient satisfaction through reduced travel to hospital outpatients.     

Revision knee arthroplasty with a rotating-hinge design in elderly patients with instability following total knee arthroplasty

Background

Revision knee arthroplasty with a rotating-hinge design could be an option for the treatment of instability following total knee arthroplasty (TKA) in elderly patients.

Purpose

To evaluate the clinical and radiographic results of revision arthroplasties in TKAs with instability using a rotating-hinge design in elderly patients.

Methods

We retrospectively reviewed 96 rotating-hinge arthroplasties. The average age of the patients was 79 years (range, 75–86 years); the minimum follow-up was 5 years (mean, 7.3 years; range, 5–10 years). Patients were evaluated clinically (Knee Society score) and radiographically (position of prosthetic components, signs of loosening, bone loss).

Results

At a minimum followup of 5 years (mean, 7.3 years; range, 5–10 years), Knee Society pain scores improved from 37 preoperatively to 79 postoperatively, and function scores improved from 34 to 53. ROM improved on average from −15° of extension and 80° of flexion before surgery to −5° of extension and 120° of flexion at the last followup (p = 0.03). No loosening of implants was observed. Nonprogressive radiolucent lines were identified around the femoral and tibial components in 2 knees. One patient required reoperation because of a periprosthetic infection.

Conclusions

Revision arthroplasty with a rotating-hinge design provided substantial improvement in function and a reduction in pain in elderly patients with instability following TKA.

Level of evidence

Level IV, therapeutic study.     

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.     

Comparison of the Clinical Outcomes after Total Knee Arthroplasty with the LCS Rotating Platform Mobile Bearing Knee System and the PFC Sigma RP-F Mobile Bearing Knee System

Background

We compared clinical outcomes after total knee arthroplasty with the Low Contact Stress (LCS) rotating platform mobile bearing knee system and the Press Fit Condylar Sigma rotating platform high flexion (PFC Sigma RP-F) mobile bearing knee system.

Methods

Fifty cases of total knee arthroplasty were performed with the PFC Sigma RP-F mobile bearing knee system and sixty-one cases were performed with the LCS mobile bearing total knee arthroplasty. The average duration of follow-up was 2.9 years.

Results

The mean Hospital for Special Surgery (HSS) knee score was 62.1 (range, 52 to 75) in the LCS group and 61.9 (range, 50 to 74) in the Sigma RP-F group preoperatively, and 90.1 (range, 84 to 100) in the LCS group and 89.8 (range, 83 to 100) in the Sigma RP-F group at the final follow-up. The mean preoperative flexion contracture was 6.7° (range, 0° to 10°) in the LCS group and 9.3° (range, 0° to 15°) in the Sigma RP-F group preoperatively. The mean range of motion was 124.6° (range, 105° to 150°) in the LCS group and 126.1° (range, 104° to 145°) in the Sigma RP-F group at the final follow-up.

Conclusions

After a minimum duration of follow-up of two years, we found no significant differences between the two groups with regard to the range of knee motion or the clinical or radiographic results.     

Prospective clinical and radiographic results of CHARITé III artificial total disc arthroplasty at 2- to 7-year follow-up: a Canadian experience

Background

Early and intermediate results have shown that the SB CHARITÉ III total disc arthroplasty (TDA) favourably compares to spinal fusion, but is associated with fewer complications and higher levels of satisfaction. We sought to prospectively report the clinical and radiographic results of the CHARITÉ III TDA after an average of 55 months follow-up.

Methods

We conducted a prospective study of patients receiving the CHARITÉ TDA at either L4–5 or L5–S1 between April 2001 and November 2006. The primary indication for surgery was discogenic low-back pain confirmed by provocative discography. Assessment included pre- and postoperative (3, 6 and 12 mo and yearly thereafter) validated patient outcome measures and radiographic review.

Results

Fifty-seven of the potential 64 (89%) patients were available for complete follow-up. Their mean age was 39 (range 21–59) years. A statistically significant improvement was demonstrated between all the mean pre- and postoperative intervals for the Oswestry Disability Index, visual analogue scale for back and leg pain, and Short Form-36 health survey (p < 0.001). The mean sagittal rotation was 6.5° (range 0.5°–22.4°), and the mean intervertebral translation was 1.1 mm (range 0–2.4 mm). Subsidence of the implant was present in 44 of 53 (83%) patients with an L5–S1 disc arthroplasty. The mean subsidence was 1.7 mm (range 0–4.8 mm).

Conclusion

The 2- to 7-year follow-up of this cohort of patients demonstrated satisfactory clinical and radiographic results in a carefully selected patient population. The radiographic assessment confirmed preservation and maintenance of motion at the replaced disc during the period of follow-up.     

Two-Stage Revision for Infected Total Knee Arthroplasty: Based on Autoclaving the Recycled Femoral Component and Intraoperative Molding Using Antibiotic-Impregnated Cement on the Tibial Side

Background

The purpose of this study was to determine the degree of infection control and postoperative function for new articulating metal-on-cement spacer.

Methods

A retrospective study of 19 patients (20 cases), who underwent a two-stage revision arthroplasty using mobile cement prosthesis, were followed for a minimum of 2 years. This series consisted of 16 women and 3 men, having an overall mean age of 71 years. During the first stage of revision, the femoral implant and all the adherent cement was removed, after which it was autoclaved before replacement. The tibial component was removed and a doughy state, antibiotic-impregnated cement was inserted on the tibial side. To achieve joint congruency, intraoperative molding was performed by flexing and extending the knee joint. Each patient was evaluated clinically and radiologically. The clinical assessments included range of motion, and the patients were scored as per the Hospital for Special Surgery (HSS) and Knee Society (KS) criteria.

Results

The mean range of knee joint motion was 70° prior to the first stage operation and 72° prior to the second stage revision arthroplasty; following revision arthroplasty, it was 113° at the final follow-up. The mean HSS score and KS knee and function scores were 86, 82, and 54, respectively, at the final follow-up. The success rate in terms of infection eradication was 95% (19/20 knees). No patient experienced soft tissue contracture requiring a quadriceps snip.

Conclusions

This novel technique provides excellent radiological and clinical outcomes. It offers a high surface area of antibiotic-impregnated cement, a good range of motion between first and second stage revision surgery for the treatment of chronic infection after total knee arthroplasty, and is of a reasonable cost.     

Reliable and reproducible technique to mark center of ankle in total knee arthroplasty

Aim

Bony and soft tissue landmarks have been used in the past to determine the center of the ankle to facilitate the tibial cut using an extramedullary guide in total knee arthroplasty. However literature reports are scanty in regards to the most ideal method available and its reproducibility in marking the center of the ankle intra-operatively.

Methods

We describe a method of using an electrocardiogram (ECG) lead in determining the center of the ankle, thus facilitating the alignment of the extramedullary guide for the tibia. Results: Using this technique, in our study the mean lateral tibial component angle was 90.09(84.2°–94.3°). The number of knees in the range of 88°–92.4° were 120 out of 122 knees (98.40%).

Conclusion

The described method is reliable and cheap, with reproducibility in determining the tibial cut in total knee arthroplasty.     

Computer-assisted navigation for the assessment of fixed flexion in knee arthroplasty

Background

Correction of a fixed flexion deformity is an important goal when performing total knee arthroplasty. The purpose of this study was to assess the accuracy of clinical assessment compared with imageless computer navigation in determining the degree of fixed flexion.

Methods

We performed navigation anatomy registration using 14 cadaver knees. The knees were held in various degrees of flexion with 2 crossed pins. The degree of flexion was first recorded on the computer and then on lateral radiographs. The cadaver knees were draped as they would be for a total knee arthroplasty, and 9 examiners were asked to clinically assess by visual observation the amount of fixed flexion. Three examiners repeated the process 1 week later.

Results

The mean error from the radiographs in the navigation group was 2.18° (95% confidence interval [CI] 1.23°–3.01°) compared with 5.57° (95%CI 4.86°–6.29°) in the observer group. The navigation was more consistent, with a range of error of −5° to +5.5° compared with −18.5° to +17.5° in the observer group. The observers tended to underestimate the amount of knee flexion (median error −4°), whereas the navigation group was more evenly distributed (median error 0). The highest concordance coefficient was found between navigation and radiography (0.96). The concordance coefficient was 0.88 for the 3 surgeons who repeated the measurements 1 week later (mean error 3.5°, range 15°).

Conclusion

The use of computer navigation appears to be a more accurate method for assessing the degree of knee flexion, with a reduced range of error compared with clinical assessment. The use of computer-assisted surgery may therefore provide surgeons with the information required to more consistently restore full extension during total knee arthroplasty.     

Limited intercarpal fusion as a salvage procedure for advanced Kienbock disease

Background

With progressive lunate collapse, salvage procedures in advanced Kienbock disease attempt to provide pain relief and maintain motion. Scaphocapitate arthrodesis may provide a durable option with comparable outcomes to proximal row carpectomy in the well-selected patient.

Methods

We performed a retrospective chart review of all consecutive patients with Lichtman stage IIIA or IIIB Kienbock’s disease who underwent either scaphocapitate or scaphotrapeziotrapezoid-capitate arthrodesis from January 2004 to December 2013.

Results

Twelve patients were included with a mean age of 41.6 years. Ten patients underwent scaphocapitate arthrodesis, while two patients underwent scaphotrapezio-trapezoid-capitate arthrodesis with an average clinical follow-up of 13.1 months. All patients achieved fusion. The average postoperative flexion-extension arc was 53° (range 20–110°). The average ulnar deviation was 9° (range 5–15°), and the average radial deviation was 13° (range 5–25°). Postoperative pain scores were significantly improved, having changed from an average of 6.6 preoperatively to 2.8 on a 10-point scale (W = 18, P < 0.05).

Conclusions

Despite a mean flexion-extension arc that is reduced from that of a normal individual, the postoperative range of motion following a midcarpal arthrodesis was not significantly different than that reported in a recent systematic review of proximal row carpectomy (73.5° compared with 53°, respectively) (P = 0.05). Additionally, given the significant postoperative reduction in associated pain symptoms at the time of follow-up, scaphocapitate arthrodesis should be considered as a treatment option for wrist salvage in the patient with advanced Kienbock’s disease.     

Bicruciate-retaining Total Knee Replacement Provides Satisfactory Function and Implant Survivorship at 23?Years

Background

One of the goals of a TKA is to approximate the function of a normal knee. Preserving the natural ligaments might provide a method of restoring close to normal function. Sacrifice of the ACL is common and practical during a TKA. However, this ligament is functional in more than 60% of patients undergoing a TKA and kinematic studies support the concept of bicruciate-retaining (that is, ACL-preserving) TKA; however, relatively few studies have evaluated patients treated with bicruciate-retaining TKA implants.

Questions/purposes

I asked: (1) what is the long-term (minimum 20-year) survivorship, (2) what are the functional results, and (3) what are the reasons for revision of bicruciate-retaining knee arthroplasty prostheses?

Methods

From January 1989 to September 1992, I performed 639 total knee replacements in 537 patients. Of these, 489 were performed in 390 patients using a bicruciate-retaining, minimally constrained device. During the period in question, this knee prosthesis was used for all patients observed intraoperatively to have an intact, functional ACL with between 15° varus and 15° valgus joint deformity. There were 234 women and 156 men with a mean age at surgery of 65 years (range, 42–84 years) and a primary diagnosis of osteoarthritis in 89%. The patella was resurfaced in all knees. The mean followup was 23 years (range, 20–24 years). At the time of this review, 199 (51%) patients had died and 31 (8%) patients were lost to followup, leaving 160 (41%) patients (214 knees) available for review. Component survivorship was determined by competing-risks analysis and Kaplan Meier survivorship analysis with revision for any reason as the primary endpoint. Patients were evaluated every 2 years to assess ROM, joint laxity, knee stability, and to determine American Knee Society scores.

Results

The Kaplan-Meier survivorship was 89% (95% CI, 82%–93%) at 23 years with revision for any reason as the endpoint. Competing-risks survivorship was 94% (95% CI, 91%%–96 %) at 23 years. At followup, the mean age of the patients was 84 years (range, 63–101 years), the mean flexion was 117° (range, 90°–130°), the mean American Knee Society score improved from a preoperative mean of 42 (range, 26–49) to 91 (range, 61–100; p < .001). Twenty-two knees in 21 patients (5.6%) were revised, most commonly because of polyethylene wear.

Conclusions

ACL sacrifice may be an unnecessary concession during TKA. This study found satisfactory survivorship and function after more than 20 years of use for patients receiving a bicruciate-retaining TKA implant. A TKA that preserves cruciate ligaments provides a stable, well-functioning knee with a low likelihood of revision at long-term followup. Retaining both cruciate ligaments during knee arthroplasty is an attractive concept that is worth considering.

Level of Evidence

Level IV, therapeutic study.     

Medial Unicompartmental Knee Arthroplasty in Patients with Spontaneous Osteonecrosis of the Knee

Background

We analyzed the clinical and radiologic results of patients with spontaneous osteonecrosis of the knee treated by minimally invasive medial unicompartmental arthroplasty using Oxford Uni.

Methods

We reviewed 22 knees in 21 patients which were treated for spontaneous osteonecrosis between 2002 and 2006. Patients included one male and 20 females. The mean age was 70.8 years (range, 53 to 82 years). The mean follow-up period was 70.3 months (range, 48 to 93 months). The clinical results were evaluated using the Hospital for Special Surgery (HSS) knee score and the range of motion of the knee preoperatively and at the final follow-up. Preoperative plain radiographs and magnetic resonance images were analyzed to determine the size and stage of osteonecrotic lesions.

Results

The mean HSS knee score was 64.3 (range, 54 to 75) preoperatively and 92.0 (range, 71 to 100) at the final follow-up. The mean preoperative flexion contracture was 8.9° (range, 0 to 15°) and 0.2° (range, 0 to 5°) at the final follow-up. The mean further flexion increased from 138.6° (range, 100 to 145°) preoperatively to 145.6° (range, 140 to 150°) at the final follow-up. Active full flexion was possible within 2 months of the operation. The squatting position was possible in 16 patients (84.2%) out of 19, except one case of bronchiectasis and one case of spine fracture. The cross-leg posture was possible in 19 patients (90.5%) out of 21. The mean tibiofemoral angle was improved from varus 0.98° to valgus 3.22°. Meniscal bearing dislocation occurred in 2 cases and femoral component loosening occurred in 1 case.

Conclusions

Unicompartmental knee arthroplasty using Oxford Uni could be an alternative treatment option in spontaneous osteonecrosis of the knee.     

Computer-assisted surgery as indication of choice: total knee arthroplasty in case of retained hardware or extra-articular deformity

Purpose

The use of traditional cutting guides during knee arthroplasty in some cases could be extremely difficult, if not impossible, because of angular deformities, IM sclerosis, long-stemmed hip implants, or hardware within the femoral canal that cannot be removed. In these difficult cases navigation-assisted knee arthroplasty should be considered as an effective and appealing option.

Methods

We present 14 cases in which ideal mechanical and prosthetic alignment was achieved with different image-free, computer-assisted navigation systems, because of an extra-articular deformity (group A, nine patients) or because of a retained implant or hardware (group B, five patients).

Results

After a mean follow-up of 28 months (range 12–53 months), the average knee score increased overall from a mean of 33 points (range 12–63) to 78 points (range 63–90). The average functional score improved from a mean of 32 points (range 10–65) to 72 points (range 40–90). The postoperative mechanical axis ranged between 3° of varus and 3° of valgus. There was an implant revision in one patient who had a traumatic rupture of medial collateral ligament, which occurred 27 months after the index procedure.

Conclusions

Based on our results we think that the navigation-assisted technique provides an alternative approach to the traditional instrumentation for treating these difficult patients in an effective and less invasive manner.     

Design Modifications May Improve Range of Motion Following Posteriorly Stabilized Total Knee Replacement: a Matched Pair Study

Background

Our institution’s latest knee implant design modifications aimed to decrease anterior knee pain, reduce the amount of bone that is resected in the femoral box, and improve range of motion.

Questions/Purposes

Does this new knee design achieve desired clinical improvement in our patient population? This study was designed to compare our new design to that of its predecessor in a matched pair analysis.

Methods

A consecutive group of 100 knees underwent total knee arthroplasty using the newer box reamer (BR) posterior-stabilized design was matched by age, gender, and body mass index (BMI) to patients with the classic posterior-stabilized (PS) component. Average follow-up was 29.6 months (range 21–47) in the new group. Preoperative range of motion (ROM) and clinical scores, such as Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Knee Society Scores, were obtained and compared to the patients’ most recent follow-up. Manipulation under anesthesia (MUA) and revision of the implant for any reason were also analyzed. Ability to attain ROM of >120°, >130°, and >140° was also determined in each cohort.

Results

At 2-year follow-up, 41% of BR knees achieved >130° flexion compared with 19% in the PS design group. WOMAC improved from pre-op 47 to 80 at 1 year in the newer BR design group and 48 to 80 in the classic PS design group. There were 9 MUAs in the newer BR design group compared with 14 in the classic PS design group. There were three revisions in the PS group and none in the BR group.

Conclusions

Design improvements to this newer knee allowed more patients to achieve greater flexion and appear to have achieved clinical and design goals of the engineering modifications.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-014-9402-z) contains supplementary material, which is available to authorized users.     

Outcome of Total Knee Arthroplasty After High Tibial Osteotomy: Does Malalignment Jeopardize the Results when Using a Posterior-Stabilized Arthroplasty?

Background

The controversy regarding the outcome of total knee arthroplasties after high tibial osteotomy may relate to malalignment secondary to overcorrection after high tibial osteotomy (HTO) [1, 2] and to the type of arthroplasty itself (posterior-stabilized arthroplasty or posterior cruciate ligament-retaining prosthesis).

Questions/Purpose

We asked two questions: (1) Would a posterior-stabilized arthroplasty provide sufficient constrain and improve pain and function in patients with severe malalignment due to a previous HTO? (2) Will malalignment of the previous HTO jeopardize the long-term results of a total knee reconstruction with a posterior-stabilized implant?

Patients and Methods

We retrospectively reviewed 25 posterior-stabilized TKAs in 25 patients with severe valgus deformity after HTO (ranging from 10° to 20° of valgus) and compared the results with a series of matched 25 posterior-stabilized TKAs in 25 patients with normocorrection after HTO ranging from 5° of valgus to 5° of varus. Clinical, operative, and radiographic data were reviewed. Minimum follow-up was 10 years after the arthroplasty (average, 15 years; range, 10–20 years).

Results

All the knees had standard posterior-stabilized total knee arthroplasty implants. Patients with an overcorrected HTO were more likely to require a soft tissue release to balance the knee. However, Average Knee Society and Function Score improved, respectively, from 48 to 85 and from 50 to 90 points in the severely overcorrected group, versus, respectively, 50 to 89 and 52 to 97 in the normocorrected group, but the range of mobility was superior for patients with normal alignment. Fifteen-year survivorship after the arthroplasty comparison showed no significant difference between the two groups (one revision in each group).

Conclusions

Patients with an overcorrected HTO are more likely to require a soft tissue release to balance the knee. However, both groups show improvements in function and pain. With a posterior-stabilized arthroplasty, the degree of deformity has no impact on the longevity of the TKA.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-013-9344-x) contains supplementary material, which is available to authorized users.     

Capitellum Fracture Fragment Excision: a Case Series

Background

Fractures of the capitellum are rare injuries, and few studies have reported the results of fragment excision.

Questions/Purposes

The purpose of this study was to determine range of motion and short-term clinical outcomes for patients treated with capitellum excision.

Methods

A retrospective review was performed to identify all patients with an isolated capitellum fracture who underwent excision as definitive treatment at our institutions. Mechanism of injury, associated elbow injuries, type of capitellum fracture, complications, and postoperative outcomes including final elbow range of motion (ROM), elbow instability, and Disabilities of the Arm, Shoulder and Hand (DASH) score were recorded.

Results

Four patients met the inclusion and exclusion criteria of this study. All patients were female with an average age of 69 years (range 42–85). Based on the Bryan and Morrey classification system, three (75%) fractures were classified as type I and one (25%) fracture as type III. The average clinical follow-up was 11 months. Final examination demonstrated a mean elbow range of motion from 14° (range 0–30) of extension to 143° (range 130–160) of flexion. All patients had full forearm rotation, and there was no clinical evidence of elbow instability. The average DASH score was 18.3 (12.5–24.2) at final follow-up.

Conclusion

Excision of the capitellum, much like excision of the radial head, results in acceptable short-term outcome scores and elbow range of motion in patients with fractures that are not amenable to open reduction and internal fixation.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-015-9452-x) contains supplementary material, which is available to authorized users.     

Mid-Term Results of Oxford Medial Unicompartmental Knee Arthroplasty

Background

This study examined the clinical and radiologic mid-term results of patients treated by Oxford minimally invasive unicompartmental knee arthroplasty.

Methods

One hundred and eighty-eight knees of unicompartmental knee arthroplasties with Oxford Uni® in 166 patients (16 males and 150 females), which were performed between 2002 and 2005, were reviewed. The mean age was 65.3 years (range, 44 to 82 years) and the mean follow-up period was 79.8 months (range, 56 to 103 months). The preoperative diagnosis was osteoarthritis in 166 patients, osteonecrosis of the medial femoral condyle in 20 and chondrocalcinosis in 2.

Results

The mean Hospital for Special Surgery (HSS) knee score was 67.5 (range, 52 to 75) preoperatively and 89.9 (range, 85 to 100) at the final follow-up. The mean preoperative flexion contracture was 6.5° (range, 0 to 15°) and 0.8° (range, 0 to 5°) at the final follow-up. The mean full flexion increased from 135° (range, 90 to 150°) preoperatively to 150° (range, 140 to 165°) at the final follow-up. Active full flexion was possible within 2 postoperative months. The squatting and cross-leg postures were possible in 133 patients (80.1%) and 152 patients (91.6%) at the final follow-up. The mean tibiofemoral angle was improved from varus 1.5° to valgus 4.8°. Complications were encountered in 18 cases (9.5%). A bearing dislocation occurred in 10 cases (5.3%), tibial component loosening in 4 cases (2.1%), femoral loosening in 3 cases (1.6%) and lateral translation in 1 case (0.5%). The mean time for a bearing dislocation was 22.6 months (range, 3 to 70 months) postoperatively. Seven cases returned to the predislocation level of activity with the insertion of a thicker bearing and 3 cases converted to total knee arthroplasty.

Conclusions

Minimally invasive unicompartmental knee arthroplasty with Oxford Uni® provided rapid recovery, good pain relief and excellent function suitable for the Korean lifestyle. In contrast, the high complication rates of Oxford Uni® encountered in the mid-term results suggested less reliability than total knee arthroplasty.     

Total knee arthroplasty using subvastus approach in stiff knee: A retrospective analysis of 110 cases

Background:

Subvastus approach used in total knee arthroplasty (TKA) is known to produce an earlier recovery but is not commonly utilized for TKA when the preoperative range of motion (ROM) of the knee is limited. Subvastus approach is known for its ability to give earlier recovery due to less postoperative pain and early mobilization (due to rapid quadriceps recovery). Subvastus approach is considered as a relative contraindication for TKA in knees with limited ROM due to difficulty in exposure which can increase risk of complications such as patellar tendon avulsion or medial collateral injury. Short stature and obesity are also relative contraindications. Tarabichi successfully used subvastus approach in knees with limited preoperative ROM. However, there are no large series in literature with the experience of the subvatus approach in knees with limited preoperative ROM. We are presenting our experience of the subvastus approach for TKA in knees with limited ROM.

Materials and Methods:

We conducted retrospective analysis of patients with limited preoperative ROM (flexion ≤90°) of the knee who underwent TKA using subvastus approach and presenting the 2 years results. There were a total 84 patients (110 knees) with mean age 64 (range 49–79 years) years. The mean preoperative flexion was 72° (range 40°–90°) with a total ROM of 64° (range 36°–90°).

Results:

Postoperatively knee flexion improved by mean 38° (P < 0.05) which was significant as assed by Student''s t- test. The mean knee society score improved from 36 (range 20–60) to 80 (range 70–90) postoperatively (P < 0.05). There was one case of partial avulsion of patellar tendon from the tibial tubercle.

Conclusions:

We concluded that satisfactory results of TKA can be obtained in knees with limited preoperative ROM using subvastus approach maintaining the advantages of early mobilization.     

Latissimus Dorsi and Teres Major Transfer With Reverse Shoulder Arthroplasty Restores Active Motion and Reduces Pain for Posterosuperior Cuff Dysfunction

Background

In patients with rotator cuff dysfunction, reverse shoulder arthroplasty can restore active forward flexion, but it does not provide a solution for the lack of active external rotation because of infraspinatus and the teres minor dysfunction. A modified L’Episcopo procedure can be performed in the same setting wherein the latissimus dorsi and teres major tendons are transferred to the lateral aspect of proximal humerus in an attempt to restore active external rotation.

Questions/purposes

(1) Do latissimus dorsi and teres major tendon transfers with reverse shoulder arthroplasty improve external rotation function in patients with posterosuperior rotator cuff dysfunction? (2) Do patients experience less pain and have improved outcome scores after surgery? (3) What are the complications associated with reverse shoulder arthroplasty with latissimus dorsi and teres major transfer?

Methods

Between 2007 and 2010, we treated all patients undergoing shoulder arthroplasty who had a profound external rotation lag sign and advanced fatty degeneration of the posterosuperior rotator cuff (infraspinatus plus teres minor) with this approach. A total of 21 patients (mean age 66 years; range, 58–82 years) were treated this way and followed for a minimum of 2 years (range, 26–81 months); none was lost to followup, and all have been seen in the last 5 years. We compared pre- and postoperative ranges of motion, pain, and functional status; scores were drawn from chart review. We also categorized major and minor complications.

Results

Active forward flexion improved from 56° ± 36° to 120° ± 38° (mean difference: 64° [95% confidence interval {CI}, 45°–83°], p < 0.001). Active external rotation with the arm adducted improved from 6° ± 16° to 38° ± 14° (mean difference: 30° [95% CI, 21°–39°], p < 0.001); active external rotation with the arm abducted improved from 19° ± 25° to 74° ± 22° (mean difference: 44° [95% CI, 22°–65°], p < 0.001). Pain visual analog score improved from 8.4 ± 2.3 to 1.7 ± 2.1 (mean difference: −6.9 [95% CI, −8.7 to −5.2], p < 0.001), and Single Assessment Numeric Evaluation score improved from 28% ± 21% to 80% ± 24% (mean difference: 46% [95% CI, 28%–64%], p < 0.001). There were six major complications, five of which were treated operatively. Overall, three patients’ latissimus and teres major transfer failed based on persistent lack of external rotation.

Conclusions

In patients with posterior and superior cuff deficiency, reverse shoulder arthroplasty combined with latissimus dorsi and teres major transfer through a single deltopectoral incision can reliably increase active forward flexion and external rotation. Patients experience pain relief and functional improvement but have a high rate of complications; therefore, we recommend the procedure be limited to patients indicated for reverse who have profound external rotation loss and a high grade of infraspinatus/teres minor fatty atrophy.

Level of Evidence

Level IV, therapeutic study.     

Scorpio single radius total knee arthroplasty. A minimal five-year follow-up multicentric study

Purpose

Our goal was to evaluate the five-year follow-up results of the Scorpio single radius total knee arthroplasty.

Method

We performed a retrospective study based upon a multicentre database to evaluate the minimum five-year follow-up clinical and radiological results of 747 patients (831 knees) who underwent primary Scorpio single radius total knee arthroplasty.

Results

The mean age of the patients was 71.9 years. At a minimal five-year follow-up, 141 patients were lost to follow-up, 83 patients had died, eight patients had undergone revision of a component, and the remaining 589 patients (602 knees) had a complete clinical and radiological evaluation after a median of six years (range, 5–8). The mean clinical component of the knee score was 92.2 points, and the mean functional component of the knee score was 76.9 points. At last follow-up, 530 of the 602 knees were rated as excellent or good. Only four knees developed patellar complications requiring revision. The survival rate at six years was 95.2% ± 1.9% and 98.3% ± 0.6 with revision for any reason and revision for mechanical failure as the end point, respectively.

Conclusion

This medium-term study indicates favourable clinical and radiological results for this single flexion-extension radius design arthroplasty, with a low complication rate on the patellar side.