Comparison of the outcomes between two different target points after open wedge high tibial osteotomy: The Fujisawa point versus the lateral tibial spine

BackgroundThe purpose of this study was to compare the clinical, radiographic and arthroscopic outcomes after open wedge high tibial osteotomy (OWHTO) aiming either at the Fujisawa point (group F) or the lateral tibial spine (LTS, group L).MethodsBetween January 2011 and May 2017, 89 cases underwent implant removal procedures with second-look arthroscopy at 19.8 months after OWHTO with first-look arthroscopy. Among them, 24 and 65 cases were enrolled in groups F and L, respectively. Outcomes included clinical (evaluated using the Western Ontario and McMaster Universities Osteoarthritis index and the International Knee Documentation Committee subjective score), radiographic (observation of the mechanical axis (MA) and tibial slope), and arthroscopic (including chondral lesions of the medial femoral condyle (MFC), trochlea, and patella scored according to the International Cartilage Repair Society grading) measures, investigated at index surgery and implant removal surgery. Outcomes were compared between two groups.ResultsPreoperative clinical characteristics and postoperative outcomes were similar between both groups. The mean postoperative MA was significantly lower in group F compared with group L (− 3.9° vs. − 1.6°, respectively; P < 0.001). Similar MFC cartilage grading changes from index surgery to second look surgery were shown; however, further progression of patellofemoral grading was shown in group F.ConclusionsOWHTO aimed at the LTS has similar clinical outcomes to Fujisawa point. Surgery aimed at the LTS was slightly less corrected. Targeting the LTS could be an option after consideration of joint geometry and patellofemoral joint problems.     

Recurrent patellar dislocations with patellar cartilage defects: A pain in the knee?

BackgroundRecurrent patellar dislocation in combination with cartilage injures are difficult injuries to treat with confounding pathways of treatment. The aim of this study was to compare the clinical and functional outcomes of patients operated for patellofemoral instability with and without cartilage defects.MethodsEighty-two patients (mean age 28.8 years) with recurrent patellar dislocations, who underwent soft-tissue or bony procedures, were divided into two matched groups (age, sex, follow up and type of procedure) of 41 each, based on the presence or absence of cartilage defects in patella. Chondroplasty, microfracture, osteochondral fixation or autologous matrix-induced chondrogenesis (AMIC)-type procedures were performed depending on the nature of cartilage injury. Lysholm, Kujala, Tegner and Subjective Knee scores of both groups were compared and analysed. Complications and return to surgery were noted.ResultsWith a mean follow up of 8 years, there was a significant improvement observed in all the mean postoperative patient-reported outcome measures of both groups, as compared with the preoperative scores (P < 0.05). Comparing the two groups, postoperative Lysholm, Kujala and Subjective knee scores were significantly higher in patients operated without cartilage defects (P < 0.05). Three patients operated for patellofemoral instability with cartilage defects underwent patellofemoral replacement subsequently. The odds ratio for developing complications was 2.53 for patients operated with cartilage defects.ConclusionAlthough there is a significant improvement in the long-term outcome scores of patients operated for recurrent patellar dislocation with cartilage defects, the results are significantly inferior compared with those without cartilage defects, along with a higher risk of developing complications and returning to surgery.     

Patient specific instrumentation allow precise derotational correction of femoral and tibial torsional deformities

BackgroundRotational malalignment deformities of the lower limb in adults mostly arise from excessive femoral anteversion and/or excessive external tibial torsion. The aim of this study was to assess the correction accuracy of a patient specific cutting guides (PSCG) used in tibial and femoral correction for lower-limb torsional deformities.MethodsForty knees (32 patients) were included prospectively. All patients had patellofemoral pain or instability with torsional malalignment for which a proximal tibial (HTO) or distal femoral (DFO) or a double-level osteotomy (DLO) had been performed. Accuracy of the correction between the planned and the postoperative angular values including femoral anteversion, tibial torsion, coronal and sagittal alignment were assessed after tibial and/or femoral osteotomy.ResultsForty knees were included in this study. In cases of HTO, the correction accuracy obtained with PSCG was 1.3 ± 1.1° for tibial torsion (axial plane), 0.8 ± 0.7° for MPTA (coronal plane) and 0.8 ± 0.6° for PPTA (sagittal plane). In cases of DFO, the correction accuracy obtained with PSCG was 1.5 ± 1.4° for femoral anteversion (axial plane), 0.9 ± 0.9° for LDFA (coronal plane) and 0.9 ± 0.9° for PDFA (sagittal plane). The IKSG was improved from 58.0 ± 13.2° to 71.4 ± 10.9 (p = 0.04) and the IKSF from 50.2 ± 14.3 to 87.0 ± 6.9 (p < 0.001).ConclusionsUsing the PSCG for derotational osteotomy allows excellent correction accuracy in all the three planes for femoral and tibial torsional deformities associated with patellofemoral instability.Level of clinical evidence II, prospective cohort study.     

Ipsilateral ACL injured patients with Segond fractures demonstrate increased posterior tibial slope

BackgroundThe anterolateral complex has been demonstrated to assist with rotational stability and prevention of anterior tibial translation during the pivot shift. In this study the Segond fracture is used as a surrogate for an anterolateral complex injury to determine if there is an association between Segond fracture and increased posterior tibial slope.MethodsPatients’ charts and radiographs were analyzed retrospectively for the presence of Segond fractures on injury radiographs. These patients, the Segond cohort, were then age and gender matched to a control cohort. Demographic as well MRI measurements of medial and lateral posterior tibial slope and lateral-to-medial slope asymmetry were collected for each cohort. Secondary outcome of anterior cruciate ligament reconstruction failure data was also collected.ResultsThe Segond group demonstrated a statistically significantly greater lateral posterior tibial slope (8.42° versus 6.55°, P = 0.003) as well as medial posterior tibial slope (6.57° versus 5.34° degrees, P = 0.045). There was no significant differences between lateral-to-medial asymmetry (2.18°versus 1.83°, P = 0.246).ConclusionPatients with Segond fractures at the time of anterior cruciate ligament injury have increased medial and lateral posterior tibial slope. This may relate to increased rotational and translational instability associated with anterolateral complex injuries. Surgeons treating these patient may use this information to counsel their patients on the risks of associated pathology at the time of arthroscopy such as lateral meniscal posterior root tears.     

Perioperative duloxetine administration reduces pain after high tibial osteotomy and non-steroidal anti-inflammatory administration: A prospective,controlled study

BackgroundPostoperative pain management is essential for patient satisfaction; however, no reports have described the effect of perioperative duloxetine administration on the postoperative pain management following knee surgery. This study aimed to determine whether perioperative duloxetine administration reduces pain following high tibial osteotomy.MethodsIn this prospective clinical trial, 35 and 33 patients receiving (40 mg/day) and not receiving duloxetine (control), respectively were enrolled. The knee pain and quality of recovery were evaluated using the numeric rating scale (NRS) scores, the frequency of analgesic drugs used, and patient-reported outcome measures, including the NRS score at rest and the Knee Injury and Osteoarthritis Outcome Score (KOOS), were compared between the groups.ResultsThe NRS scores of the duloxetine group (D) were significantly reduced compared with those of the control group (C) on postoperative day 1 (D:3.8 vs C:5.1, p = 0.022), day 7 (D:2.1 vs C:2.9, p = 0.021), and day 14 (D:1.6 vs C:2.9, p = 0.001). Non-steroidal anti-inflammatory drug administration was significantly lower in the duloxetine group than in the control group (p < 0.001). Although the KOOS score was not significantly different in several subcategories at the pre- and postoperative time-points, the Function in Sport subcategory of the KOOS was significantly improved in the duloxetine group compared with that in the control group at 3 months postoperatively (p < 0.05).ConclusionPerioperative use of duloxetine from 2 weeks before surgery to 2 weeks after surgery is advantageous in perioperative pain management and KOOS improvement following high tibial osteotomy.     

Comparative outcomes of patient-specific instrumentation,the conventional method and navigation assistance in open-wedge high tibial osteotomy: A prospective comparative study with a two-year follow up

BackgroundTo compare and analyze the correction precision, clinical outcomes and complications among the three methods of performing open-wedge high tibial osteotomy (HTO), including patient-specific instrumentation (PSI), conventional method and navigation assistance.MethodsIn this prospective, single-center study, we randomly assigned patients with knee osteoarthritis in a 1:1:1 ratio to undergo Open-wedge high tibial osteotomy (OWHTO) with conventional method, navigation assistance or PSI. The primary outcome was the target/observed hip–knee–ankle (HKA) angle difference at 1 month postoperatively. Secondary outcomes were changes in the postoperative posterior tibial slope (PTS) at 1 month and clinical outcomes including knee pain on a visual analogue scale (ranging from 0 to 100, with higher scores indicating more severe pain), Lysholm and Western Ontario and McMaster Universities Osteoarthritis Index (ranging from 0 to 240) scores at 1 month, 6 months, 12 months, and 24 months.ResultsFrom 2017 through 2019, a total of 608 patients were screened; of those patients, 144 were enrolled, with 48 in each group. The primary outcome of the HKA difference was 2.6 ± 2.0° in the conventional group, 2.3 ± 1.5° in the navigation group and 0.6 ± 1.0° in the PSI group (P < 0.001). Secondary outcomes including changes in the postoperative PTS and clinical outcomes at 1 month, 6 months, and 12 months were in the same direction as the primary outcome. There were no significant differences in the complications among the three groups.ConclusionsIn the present study, none of the three methods showed superiority in objective correction precision and clinical outcomes at 2 years.     

Medial closing-wedge distal femoral varus osteotomy: Symptoms and functional impact in cases of associated patellofemoral osteoarthritis. A two-year follow-up prospective pilot study

PurposeTo date, indications for distal femoral varus osteotomy (FVO) in cases of associated patellofemoral osteoarthritis (PFO) have yet to be clarified. The purpose of this prospective study is to assess the short-term symptoms, functional and radiological impact of a medial closing-wedge femoral varus osteotomy on the patellofemoral joint in patients with valgus deformities who are afflicted with lateral tibiofemoral osteoarthritis (LTFO) associated with PFO.MethodsFourteen patients (15 knees) received a medial closing-wedge femoral varus osteotomy. The functional impact of an FVO on the patellofemoral joint was assessed based on the KOOS-PF (Knee Injury and Osteoarthritis Outcome Score-Patellofemoral Subscale), the Kujala score and the patellofemoral symptoms. Realignment of the patella was measured by the Merchant's patellofemoral congruence angle. The pre- and post-operative symptoms and functional scores were compiled prospectively and compared two years after the surgery.ResultsThe Kujala patellofemoral functional scores and the KOOS-PF showed considerable improvement with a differential of + 37.5 points ± 20.4 and + 42.7 points ± 19.3 (p < .01) respectively. The average Merchant's congruence angle went from 8.8° laterally to 3.6° medially, resulting in medialization of the patella, with a significant difference (p < .01). Based on the specific clinical analysis of the patellar joint, preoperative J-sign was identified in 26.7% of patients (n = 4) and was not found during postoperative examination (p = .1). Preoperative apprehension test was identified in 33.3% of patients (n = 5) against 13.3% (n = 2) after surgery (p = .39). Preoperative pain extension test was identified in 40% of patients (n = 6) against 20% during postoperative clinical analysis (p = .43).DiscussionAlthough the threshold of significance for patellofemoral symptoms was not reached, the medial closing-wedge femoral varus osteotomy induces a significant medialization of the patella (Merchant's congruence angle) and improves short-term functional results even with co-existing patellofemoral osteoarthritis. Due to the lack of specificity of the patellofemoral scores, patellofemoral osteoarthritis improvement is difficult to determine on its own, but does not represent a contraindication to FVO.Level of evidenceIII. Prospective clinical study.     

Patellar cartilage loss does not affect early outcomes of total knee arthroplasty performed without patella resurfacing

BackgroundThe aim of this study was to compare the outcomes and cost economics of TKA without patella resurfacing in patients with and without patellar cartilage loss.MethodsProspective case control study of 209 consecutive patients undergoing TKA without patella resurfacing. Patella cartilage status was documented intra-operatively: 108 patients had patella cartilage loss (mean age 70 ± 9.7, mean BMI 31 ± 6.2, 72 (67%) female) and 101 control patients did not (age 68 ± 9.2, BMI 31 ± 5.6, 52 (51%) female). The primary outcome measure was Oxford Knee Score (OKS) improvement at one year. Secondary outcomes included OKS, EQ-5D, anterior knee pain (AKP), Kujala scores and reoperation at 2–4 years. The cost to prevent secondary patella resurfacing was calculated.ResultsThere were more women in the patella cartilage loss group (67% Vs 51%, p = 0.037), but no other preoperative characteristics differed. There was no difference in OKS improvement between those with and without patella cartilage loss at 1 year (mean difference −1.03, −3.68 to 1.62 95%CI, p = 0.446) or 2–4 years (mean difference 1.52, −1.43 to 4.45 95%CI, p = 0.310). At 2–4 years there was no difference in AKP (14/87 with vs 17/80 without, p = 0.430) nor Kujala score (mean difference 2.66, −3.82 to 9.13 95%CI, p = 0.418). Routine patella resurfacing would have cost £58,311 to prevent one secondary resurfacing.ConclusionThere was no difference in OKS, anterior knee pain, reoperation or Kujala scores up to 2–4 years between patients with and without patellar cartilage loss following TKA without patella resurfacing. Resurfacing for this indication would not have been a cost effective intervention.     

Aiming for anatomical femoral axis on the coronal plane leads to good-to-excellent short-term outcomes in isolated patellofemoral arthroplasty

BackgroundIn patellofemoral replacement (PFR) coronal alignment is mostly influenced by local condylar anatomy. However, there is still a lack of consensus regarding references to follow intraoperatively for the optimal positioning of the trochlear component. The aim of this study was to assess whether aiming for the anatomical femoral axis on the coronal plane leads to improved clinical outcomes and whether coronal alignment correlates with clinical outcomes.MethodsForty-two patients who underwent PFR were retrospectively evaluated at a minimum one-year follow-up using Kujala and Knee Society Score (KSS). Moreover, patients underwent an anteroposterior hip-to-knee X-ray to evaluate the coronal alignment of the trochlear component with respect to the femoral anatomic and mechanical axis. Prosthesis coronal alignment, Kujala, and KSS were assessed for possible correlation.ResultsMean follow-up time: 29.1 months. Mean KSS for pain: 90 (± 8.9), for function: 93.7 (± 15.9); mean Kujala: 89.2 (± 13.6). Mean prosthesis coronal alignment was 3.3 ± 2.3° in valgus with respect to the femoral anatomic axis and 7.4 ± 2.6° in valgus with respect to the femoral mechanical axis. No correlations were found between coronal alignment and KSS or Kujala scores.ConclusionsResults from the current study showed that PF replacement with a third-generation implant led to good-to-excellent outcomes. In addition, the surgical technique used for aligning femoral component in this study resulted in reduced coronal alignment variability and achieved good short-term clinical outcomes.     

Tibial tubercle proximalization as quadriceps lengthening in treating severe habitual patellar dislocation in adults

BackgroundTo describe a novel ‘four-in-one’ procedure – including tibial tubercle proximalization, extensive lateral release, tibial tubercle medialization, and medial patellofemoral ligament reconstruction – for treating severe habitual patellar dislocation (HPD) in adults, and to report its early clinical outcomes.MethodsThirteen patients (13 knees) with severe primary HPD received this procedure. Results of the physical examinations, including apprehension tests and patellar tracking throughout full range of motion, were recorded pre-operatively and at final follow-up. Radiological assessments included standard anteroposterior view, true lateral view at 30° knee flexion, axial views of the patellofemoral joint at both 30° and maximum angle of knee flexion, and computed tomography scans at full knee extension pre-operatively and at final follow-up. Subjective patellofemoral functions were evaluated with the Kujala functional score before the index procedure and at final follow-up visit.ResultsAll 13 patients were followed for an average period of 35.5 months (range, 25–49). After the index ‘four-in-one’ procedure no patient reported reoccurrence of patellar dislocation at the final follow-up visit. Radiographically, there was a statistically significant improvement in the congruence angle from 75.2 ± 16.3° pre-operatively to ? 7.2 ± 5.4° postoperatively (P < 0.01) and in the lateral patellofemoral angle from ? 66.3 ± 8.3° pre-operatively to 6.3 ± 2.6° postoperatively (P < 0.01). The average pre-operative Kujala functional score was 41.4 and average postoperative score was 94.9 (P < 0.05).ConclusionThe novel ‘four-in-one’ procedure effectively treated HPD in adults with severe quadriceps contracture.     

Medialization of the mechanical axis of the tibia is related to lateralization of the tibial tuberosity in knee osteoarthritis

PurposeTo determine whether medialization of the proximal tibia due to a varus deformity is related to lateralization of the tibial tuberosity in varus knee osteoarthritis (OA).MethodsA total of 120 knees that underwent osteotomies around the knee for varus knee OA were enrolled. Mechanical medial proximal tibial angle (mMPTA) was measured on radiographs. The angle between the mechanical and anatomical axes of the tibia (angle MA) and the distance between the centre of the tibial plateau and the anatomical axis (distance MA) were measured in the coronal plane on computed tomography images. The tibial tuberosity–posterior cruciate ligament (TT-PCL) distance, the distance between the midpoint of the tibial tuberosity and the centre of the tibial plateau (TT-centre distance), and the angle between the line through the midpoint of the tibial tuberosity and the centre of the tibial plateau and the anteroposterior axis (TT-centre angle) were measured in the axial plane. The correlations of these parameters were evaluated.ResultsmMPTA correlated negatively with angle MA (r = −0.37, P < 0.01) and distance MA (r = −0.55, P < 0.01). Angle MA and distance MA correlated with TT-PCL distance (r = 0.39, P < 0.01, r = 0.42, P < 0.01), TT-centre distance (r = 0.35, P < 0.01, r = 0.38, P < 0.01) and TT-centre angle (r = 0.36, P < 0.01, r = 0.36, P < 0.01).ConclusionsMedialization of the proximal tibia due to a varus deformity may induce lateralization of the tibial tuberosity.     

Combined deepening trochleoplasty and supracondylar external rotation osteotomy for recurrent patellar instability in patients with trochlear dysplasia and increased femoral antetorsion

BackgroundDeepening trochleoplasty has become a part of surgical management in patients with patellar instability and severe trochlear dysplasia. In addition, increased femoral antetorsion is treated most commonly by proximal femoral external rotation osteotomy.HypothesisDeepening trochleoplasty and supracondylar femoral external rotation osteotomy in combination improve patellar stability and function in patients presenting with recurrent patellar instability due to trochlear dysplasia and increased femoral antetorsion.Study designTherapeutic case series; Level IV.MethodsCombined deepening trochleoplasty and supracondylar external rotation osteotomy were performed in seven female patients (nine knees) with recurrent patellar instability. Trochlear dysplasia (Dejour classification) and increased femoral antetorsion (Murphy computed tomography (CT)-based measurement) were documented using magnetic resonance imaging and CT scans. Data were collected prospectively preoperatively, at 12 months, and at final follow-up. Complete data were available in 100% of cases. Clinical and functional outcomes were evaluated using the Kujala score and Tegner activity level scale.ResultsThe average age at the time of surgery was 22.2 years (range, 17–29 years). Preoperative MRI-based findings demonstrated in all patients significant trochlear dysplasia (B in two, C in five, and D in two knees). Femoral antetorsion was 37.8° on average (range, 27–51°). The mean follow-up was 2.1 years after surgery (range, 1–5.5 years). The median Kujala score was 41.2 preoperatively, rising to 83.1 at final follow-up (P = .015). The Tegner activity score improved from a mean preoperative score of 2.7 to a mean postoperative score of 6.0 (P = .020). Good patellar stability without positive apprehension sign was found in all patients. Poor outcome was associated with significant patellofemoral cartilage damage (grade IV) at the time of surgery. A total of 88.8% of patients were satisfied with the knee function at final follow-up. There were no postoperative complications.ConclusionThe combination of deepening trochleoplasty and supracondylar external rotation osteotomy performed in one step is an individually adapted surgical procedure for restoring both horizontal limb alignment and trochlear geometry. It improves patellar stability and yields good subjective and objective functional results in most cases. The condition of the cartilage at the time of surgery is crucial for the outcome with respect to the pain.     

Trochleoplasty for severe trochlear dysplasia significantly improves the quality of life of patients with symptomatic patellar instability

BackgroundTrochleoplasty is a recognized surgical technique to address severe trochlear dysplasia. The clinical and radiological outcomes of trochleoplasty surgery in trochlear dysplasia have been well reported. There is a paucity in literature regarding the correlation between trochleoplasty and quality of life (QoL). The aim of this study is to measure the improvement in QoL, in patients with severe trochlear dysplasia and recurrent patellar instability following trochleoplasty.MethodsBetween 2013 and 2019, 51 trochleoplasty cases were performed in 48 patients. They were identified from our prospectively kept database. All operations were performed by a fellowship trained consultant sports knee surgeon. Functional outcomes and QoL scores were assessed using Kujala, IKDC and EQ-5D index. Objective outcomes were obtained following each patient’s latest follow-up assessment.ResultsThe mean age at operation was 22y (SD ± 4.7, range 14–37y) and the mean follow-up period was 21.6 months (SD ± 15.2, range 12–60 months). The mean Kujala score improved from 58.1 (SD 14.9) to 77.9 (SD 17.3) at latest follow-up (p < 0.001). The mean IKDC score improved from 40.5 (SD 14.2) to 69.5 (SD 22.8) at latest follow up (p < 0.001). The mean EQ-5D index also improved from 0.593 (SD 0.257) to 0.824 (SD 0.189) at latest follow-up (p = 0.003). A higher Body Mass Index (BMI; >30 kg/m²) was associated with inferior outcomes.ConclusionTrochleoplasty is an effective surgical technique which improves the QoL in patients suffering from patellar instability secondary to severe trochlear dysplasia. BMI can be used to predict post-operative outcomes.     

Anterior and rotational tibial subluxation in the setting of anterior cruciate ligament injuries: An MRI analysis

BackgroundThe relationship between preoperative tibiofemoral position and failure of anterior cruciate ligament (ACL) reconstruction has been widely discussed. Most established methods for measuring tibiofemoral position on magnetic resonance imaging (MRI) mainly focus on anterior tibial subluxation (ATS), while a quantitative measuring method for rotational tibial subluxation (RTS) is still undetermined. Moreover, there are still controversies about the related factors for ATS. The aim of this study was to quantitatively describe preoperative ATS and RTS in ACL-injured and ACL-intact knees and identify the related factors for ATS and RTS based on MRI images.MethodsDemographic data and preoperative MRIs of 104 ACL-injured patients were retrospectively analyzed. ACL-intact knees were 1:1 matched as control group. ATS was measured using longitudinal tibial axis, and RTS was determined by the difference between lateral and medial ATS. Related factors for ATS and RTS were examined.ResultsIncreased lateral ATS (P < 0.0001), medial ATS (P < 0.0001) and RTS (P = 0.0479) were observed in ACL-injured knees compared with the control group. Increased posterior tibial slope (PTS), Beighton Score ≥ 4, presence of meniscal injury and long injury-to-MRI time were identified as being correlated with the increase of ATS. Factors for the increase of RTS were increased lateral PTS, Beighton score ≥ 4, presence of lateral meniscal injury, and left side.ConclusionsIn ACL-injured knees, tibia not only subluxated anteriorly in both lateral and medial compartments, but also rotated internally. During preoperative planning, attentions should be paid to the factors that are correlated with altered tibiofemoral position.     

Delayed but favourable outcome of lateral tibial plateau fracture after screw fixation: A 3-year prospective cohort study of 56 patients

BackgroundAlthough a large number of studies aimed to investigate the outcome following lateral tibial plateau fractures, the literature includes limited information on mid- to long-term follow up. The primary objective of the present study was to investigate the 3-year development in Knee Injury and Osteoarthritis Outcome Score (KOOS₅) of patients with surgically managed lateral tibial plateau fractures.MethodsProspective cohort study. The study includes all patients treated surgically following a lateral tibial plateau fracture (AO-41B) in the period December 2013 to November 2016. The primary outcome measurement was the patient-reported KOOS₅ score. Secondary outcome measurements were quality of life, knee osteoarthritis, muscle strength, pain reactions, and gait function.ResultsFifty-six patients were included. Thirty-nine patients were eligible for the 3-year follow up (70%). The mean age at the time of the 3-year follow up was 58.3 years with a range of 25–89. The 3-year postoperative mean KOOS₅ scores were 75.5 (95% confidence interval: 68.6–82.3). Compared with the KOOS₅ score at 12-month follow up (61.3), a significant increase was observed (P > 0.001). In comparison with the established KOOS reference population, the study population showed statistically worse KOOS outcomes only for the subscale sport.ConclusionsPatient-reported outcome (KOOS₅) among patients with a fracture of the lateral tibial plateau increased significantly between the 1-year and 3-year follow ups. In contrast to the 1-year follow up, patients at the 3-year follow up reported results comparable to those of a healthy reference population, excluding the Sport subscale. Guiding the patients in anticipation of a prolonged recovery period is highly important in everyday clinical practice.     

Focal proximal fibular angle: A potential indicator of the tibial mechanical axis in opening-wedge high tibial osteotomy

BackgroundFor opening-wedge high tibial osteotomy, correct alignment is essential for a better prognosis. It is difficult to evaluate the mechanical axis of the lower extremity or tibia using a single fluoroscopic image. This study aimed to discuss the use of focal proximal fibular angle (FPFA), which can be assessed by a single fluoroscopic image, as an intraoperative indicator.MethodsEligible for analyses were 111 consecutively treated patients; for the final analyses 96 patients were included. The preoperative and postoperative medial proximal tibial angle (MPTA) and FPFA were measured. The relationship between these two angles, correction amount, weight-bearing line ratio and patient characteristics were analyzed.ResultsThe preoperative FPFA and MPTA were 96.5 ± 3.8° (mean ± standard deviation, SD) and 84.8 ± 3.0°, while the postoperative FPFA and MPTA were 87.6 ± 4.1° and 94.0 ± 3.5°, respectively. The preoperative and postoperative sums of the MPTA and FPFA were constant. The discrepancy was less than 3° in all knees, less than 2° in 92.7% knees and less than 1° in 68.8% knees. It was not correlated with age, sex, weight-bearing line ratio, or correction amount.ConclusionThe study findings confirmed the constancy of the sum of the MPTA and FPFA. The FPFA can be easily evaluated on a single fluoroscopic image of the knee. Use of the FPFA as guidance may simplify the procedure of opening-wedge high tibial osteotomy and approximately predict the tibial mechanical axis.     

Simultaneous bilateral opening-wedge high tibial osteotomy with structural allograft impaction results in excellent early recovery and pain reduction similar unilateral osteotomy

BackgroundPatients suffering from bilateral combined medial osteoarthritis and varus alignment of the knee are eligible for bilateral high tibial osteotomy (HTO) in two-staged surgery. The impact of bilateral HTO surgery on rehabilitation and early outcomes have not yet been reported in the literature, even though these features are decisive in establishing whether a patient is preferably treated in one or two stages.MethodsA total of 29 patients were followed after simultaneous bilateral HTO surgery. Numeric Rating Scale (NRS), Knee injury and Osteoarthritis Outcome Score – Physical Function Short Form (KOOS-PS) and Lysholm scores were recorded at 3, 6 and 12 months. Results were compared with outcomes of unilateral HTO surgery to asses the additional impact of simultaneous bilateral HTO surgery on the early rehabilitation and recovery of simultaneous bilateral HTO surgery.ResultsThree months after surgery, NRS pain scores decreased from 60.5 to 40.9 and subsequently to 30.4 and 24.3 after 6 and 12 months, respectively. KOOS-PS scores improved from 50.0 to 44.3 after 3 months, to 33.9 and 29.8 after 6 and 12 months, respectively. Lysholm scores did not improve after 3 months (45.2–44.2), but significantly improved after 6 and 12 months (66.1 and 75.7, respectively). Compared with unilateral HTO surgery, similar improvements were seen after 6 and 12 months.ConclusionSimultaneous bilateral HTO surgery generates similar clinical outcomes compared with unilateral HTO surgery and moreover it does not excessively prolong time to achieve these outcomes. It is safe and presumably a more effective approach to treat patients suffering bilateral medial osteoarthritis and varus alignment of the knee compared with two-staged surgery.     

Thinner tuberosity osteotomy is more resistant to axial load in medial open-wedge distal tuberosity proximal tibial osteotomy: A biomechanical study

BackgroundThe purpose of this study was to investigate axial load resistance of the tibia depending on the thickness of tibial tuberosity osteotomy in medial open-wedge distal tuberosity proximal tibial osteotomy (OWDTO). The hypothesis is that a thin tibial tuberosity osteotomy shows high axial load resistance of the tibia.MethodsThe OWDTO model was constructed from imitation bones of the tibia. Distal tibial tuberosity osteotomy was performed with thicknesses of 7, 14, and 21 mm (n = 5 for each group). Cyclic axial-load fatigue tests were performed to investigate the strain at five measurement points on the OWDTO model. An axial-load failure test was also performed to investigate the maximum strain for failure.ResultsThe 7-mm OWDTO model showed a significantly lower stain range than the 14-mm model at the middle part of the lateral hinge (P = 0.0263, mean difference: −852.6 με), posterior part (P = 0.0465, mean difference: −1040.0 με), posterior tibial cortex (P < 0.0001, mean difference: −583.4 με), and plate (P = 0.0029, mean difference: −121.6 με). There were no significant differences in the strain at the tibial tuberosity between the groups. The axial load for complete failure was significantly higher in the 7-mm model than in the 21-mm model (P = 0.0010, mean difference: 2577.0 N). The failure points were at the lateral hinges.ConclusionsThinner distal tibial tuberosity osteotomy is more resistant to axial load and may be recommended for the prevention of tibial and lateral hinge fractures after OWDTO.     

Psychometric properties of the Norwich Patellar Instability Score in people with recurrent patellar dislocation

BackgroundPatellar dislocations account for two percent of all knee injuries with a 17% chance of re-dislocation. There are few validated scores specific to instability. One of these is the Norwich Patellar Instability Score. There has been limited assessment of the validity, floor-ceiling effect and responsiveness of the Norwich Patellar Instability (NPI) Score from an independent centre. The purpose of this paper is to address this limitation.MethodsData from 90 patients referred to a tertiary referral patellofemoral clinic were analysed. All routinely completed data including NPI Score, Kujala Patellofemoral Disorder Score, and demographic outcomes during appointments, up to 36 months following initial clinical assessment was analysed. Convergent validity was assessed by correlating outcomes of the Kujala Patellofemoral Disorder Score to the NPI Score. Effect size (ES) was determined between baseline to 12-month and 12 to 36-month assessments to determine responsiveness. Floor-ceiling effect was evaluated at baseline, 12-month and 12 to 36-month follow-up.ResultsNPI Score demonstrated good convergent validity to the Kujala Patellofemoral Disorder Score (p < .001; 95% confidence interval (CI): − 0.71 to − 0.52). NPI Score demonstrated good responsiveness to change both between baseline to 12 months (ES: 0.43; 95% CI: 0.42 to 0.10) and 12 to 36 months (ES: 0.67; 95% CI: 0.60 to 0.15). Whilst the NPI Score did not demonstrate a ceiling effect, there was moderate risk of a floor-effect where 13% of the cohort reported the lowest levels of NPI scores.ConclusionsThe NPI Score is a valid and responsive outcome for people with recurrent patellar dislocation.