Better clinical outcomes and return to sport rates with additional medial meniscus root tear repair in high tibial osteotomy for medial compartmental knee osteoarthritis.

PURPOSE: This retrospective study aimed to investigate whether the repair of medial meniscus posterior root tears (MMPRTs) is effective for improving clinical outcomes and return to sports rates in young patients (50 years old or younger) with medial compartment knee osteoarthritis (KOA) and MMPRTs. METHODS: Between 2016 and 2019, 153 patients with KOA and MMPRTs who underwent open-wedge high tibial osteotomy (OWHTO) were retrospectively included. The patients were divided into OWHTO combined with MMPRT repair (n = 73) and isolated OWHTO (n = 80) groups. Lysholm scores, Hospital for Special Surgery (HHS) scores, Tegner scores, flexion contracture, range of knee flexion, return to sports rates and postoperative complications were compared. Radiological outcomes, including hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), joint line convergence angle (JLCA) and Kellgren-Lawrence (K-L) grade, were compared between the two groups. RESULTS: After a mean follow-up of 30.1 ± 3.0 months, the OWHTO + Repair group observed better clinical outcomes compared with the OWHTO group (Lysholm score: 86.7 ± 7.4 vs. 81.6 ± 6.9, p = 0.023. HHS score: 85.4 ± 8.20 vs. 80.5 ± 7.1, p = 0.039). The OWHTO + Repair group had higher Tegner scores and return to sports rates than the OWHTO group (Tegner score: 6 vs. 5, p = 0.020; return to sports rates: 38% vs. 15%, p = 0.001). No fracture or major complications occurred. Radiological outcomes showed no significant differences between the two groups (HKA: 181.1 ± 2.7 vs. 180.1 ± 1.5 n.s; MPTA: 90.1 ± 1.8 vs. 89.2 ± 1.4, n.s; JLCA:1.9 ± 0.7 vs. 2.1 ± 0.7, n.s). CONCLUSIONS: Additional MMPRT repair during OWHTO was associated with better clinical outcomes and higher rates of return to sports in young patients with medial compartment KOA and MMPRTs. LEVEL OF EVIDENCE: Level III.

Improved 2-Year Freedom from Arthroplasty in Patients with High-Risk SIFK Scores and Medial Knee Osteoarthritis Treated with an Implantable Shock Absorber versus Non-Operative Care.

OBJECTIVE: Subchondral insufficiency fracture of the knee (SIFK) is associated with high rates of osteoarthritis (OA) and arthroplasty. The implantable shock absorber (ISA) is an extra-capsular implant that unloads the medial knee compartment. This study compared the 2-year freedom from arthroplasty rates in subjects with medial knee OA and SIFK when treated with an ISA versus a matched cohort of patients treated non-surgically. DESIGN: This retrospective case-control study compared 2-year conversion rates to arthroplasty in SIFK score-, age-, and body mass index (BMI)-matched control subjects without prior surgical history with ISA-implanted subjects from an ongoing prospective study. Baseline and final radiographs, and MRIs were reviewed for evaluation of meniscus or ligament injuries, insufficiency fractures, and subchondral edema. Kaplan-Meier analysis assessed survival. RESULTS: Forty-two patients (21 Control: 21 ISA), mean age = 52.3 ± 8.7 years, BMI = 29.5 ± 3.9 kg/m2, 40% female were evaluated. Both ISA and Control arms had the same numbers of low (n = 4), medium (n = 11), and high-risk (n = 6) SIFK scores. One- and 2-year freedom-from-arthroplasty rates were both 100% for ISA subjects, and 76% and 55%, respectively, for Controls (P = 0.001 for cross-group comparison). Control knees with low, medium, and high-risk SIFK scores had respective 1- and 2-year survival rates of 100% and 100%, 90% and 68% (P = 0.07 vs. ISA), and 33% and 0% (P = 0.002 vs. ISA). CONCLUSIONS: ISA intervention was strongly associated with avoidance of arthroplasty at a minimum 2 years, especially in patients with high-risk SIFK scores. SIFK severity scoring predicted relative risk of conversion to arthroplasty through at least 2 years in non-surgically treated subjects.

An implantable shock absorber yields an 85% survival-from-arthroplasty rate through 5 years in working-age patients with medial compartment knee osteoarthritis.

PURPOSE: To evaluate the 5-year rate of survival without undergoing arthroplasty or high tibial osteotomy (HTO) in subjects with mild-to-moderate medial compartment knee osteoarthritis (OA) who were treated with an implantable shock absorber (ISA) system. METHODS: Three prospective, sequential, multicenter, international, single-arm clinical trials were conducted comprising subjects who received an ISA for symptomatic medial knee OA after failing ≥ 6 months of conservative therapy. Study outcomes were analyzed cumulatively and by enrollment group when all subjects' follow-up data exceeded the 2-year threshold after ISA implantation. Primary outcome was survival rate without conversion to arthroplasty/HTO. Secondary outcomes were changes in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores after ISA implantation. RESULTS: All 171 enrolled subjects (age 51 ± 9 years, body-mass index 28.5 ± 3.5 kg/m2, 38% female; study knee Kellgren-Lawrence score 2.7 ± 0.9 points) were followed for a minimum of 2, and up to 5, years after device implantation. Overall, 90.6% (155/171) of subjects survived without requiring arthroplasty/HTO at last follow-up (mean 3.2 ± 1.6 years). The Kaplan-Meyer median 3- and 5-year survival-without-arthroplasty point estimates were 89.8% (95% CI 86.5‒95.7%) and 84.9% (95% CI 75.1‒91.1%), respectively. The median 3-year estimated survival rate for the most recent study (n = 81) was 97.3%. The mean WOMAC Pain score decreased 71% from baseline to last follow-up after ISA implantation, from 58 ± 13 to 16 ± 17 points (p < 0.0001). The Function score improved 69%, decreasing from 56 ± 18 to 17 ± 17 points (p < 0.0001). CONCLUSIONS: In younger patients with mild-to-moderate symptomatic medial compartment knee OA, implantation of the ISA device resulted in a 5-year survival rate of 85% from undergoing arthroplasty or HTO. The ISA system may be an effective treatment option for working-age patients with medial knee OA who are not candidates for or do not desire more invasive surgical approaches. LEVEL OF EVIDENCE: II.

Assessment of fore-, mid-, and rear-foot alignment and their association with knee symptoms and function in patients with knee osteoarthritis.

OBJECTIVE: Hallux valgus, flatfoot, and rearfoot eversion are well-known major complications of knee osteoarthritis (OA). However, there is no consensus on the association between these foot malalignments and knee symptoms or function. Thus, this study aimed to examine the association between foot alignment and knee symptoms or function in patients with knee OA. METHODS: Female patients aged ≥ 50 years with symptomatic knee OA participated in this study. Knee symptoms and function were assessed using the Knee Society Scoring System (KSS). Hallux valgus, navicular/foot ratio, and leg heel alignment were used as the forefoot, midfoot, and rearfoot alignment indices, respectively. The navicular/foot ratio was defined as the ratio of the navicular height to the total foot length. We performed multiple linear regression analysis to examine the associations between foot alignment and knee symptoms or function. RESULTS: Seventy-eight participants participated our study. KSS symptom score was significantly associated with navicular/foot ratio (regression coefficient [ß], -0.30; 95% confidence interval [CI], -109.2 to -20.5; P = 0.005), knee extensor strength (ß, 0.32; 95% CI, 0.02 to 0.09; P = 0.004), and age (ß, 0.24; 95% CI, 0.01 to 0.32; P = 0.036). KSS function score was not associated with foot alignments but with knee extensor strength (ß, 0.40; 95% CI, 0.10 to 0.33; P = 0.001) and body mass index (ß, -0.35; 95% CI, -2.82 to -0.66; P = 0.002). CONCLUSIONS: Knee symptoms were significantly associated with midfoot alignment in patients with medial knee OA. This suggests that lower navicular height in patients with medial knee OA may relate with the alleviation of knee symptoms. Key Points • In patients with medial knee OA, midfoot alignment was significantly associated with knee symptoms in patients with medial knee OA; however, knee function was not associated with foot alignment. • Lower navicular height in patients with medial knee OA may relate with the alleviation of knee symptoms.

Severe varus knees result in a high rate of undercorrection of lower limb alignment after opening wedge high tibial osteotomy.

PURPOSE: The purpose of this study was to clarify the indication for opening wedge high tibial osteotomy (OWHTO) in terms of lower limb alignment to achieve satisfactory clinical results. METHODS: Ninety-two patients (98 knees) with medial compartment knee osteoarthritis were investigated in this study. The average follow-up period was 34 months (range, 24-68 months). The average age of the patients at the time of surgery was 63 years (range, 41-77 years). RESULTS: The patients were divided into the following two groups according to the preoperative femorotibial angle (FTA) on anteroposterior full-length radiographs of the lower limbs while weight bearing: 29 knees with a preoperative FTA of ≥185° were defined as those with severe varus (S group), and the remaining 69 knees with a preoperative FTA of <185° were defined as those with mild varus (M group). Knees with a postoperative FTA of >175° were defined as undercorrected. The Lysholm score was used to assess the clinical results. The average postoperative FTA was 175.7° ± 4.1° in the S group and 174.6° ± 3.1° in the M group ( p = 0.013). Significantly, more undercorrected knees were observed in the S than M group ( p = 0.00035). The postoperative Lysholm score was 85.6 ± 8.5 in the S group and 88.5 ± 5.7 in the M group at the last follow-up ( p = 0.0033). CONCLUSION: Based on these results, we recommend that a preoperative FTA of <185° should be included as a criterion for OWHTO alone.

Gait alteration strategies for knee osteoarthritis: a comparison of joint loading via generic and patient-specific musculoskeletal model scaling techniques.

Gait modifications and laterally wedged insoles are non-invasive approaches used to treat medial compartment knee osteoarthritis. However, the outcome of these alterations is still a controversial topic. This study investigates how gait alteration techniques may have a unique effect on individual patients; and furthermore, the way we scale our musculoskeletal models to estimate the medial joint contact force may influence knee loading conditions. Five patients with clinical evidence of medial knee osteoarthritis were asked to walk at a normal walking speed over force plates and simultaneously 3D motion was captured during seven conditions (0°-, 5°-, 10°-insoles, shod, toe-in, toe-out, and wide stance). We developed patient-specific musculoskeletal models, using segmentations from magnetic resonance imaging to morph a generic model to patient-specific bone geometries and applied this morphing to estimate muscle insertion sites. Additionally, models were created of these patients using a simple linear scaling method. When examining the patients' medial compartment contact force (peak and impulse) during stance phase, a 'one-size-fits-all' gait alteration aimed to reduce medial knee loading did not exist. Moreover, the different scaling methods lead to differences in medial contact forces; highlighting the importance of further investigation of musculoskeletal modeling methods prior to use in the clinical setting.

Evidence and mechanism by which upper partial fibulectomy improves knee biomechanics and decreases knee pain of osteoarthritis.

To investigate the change in short-term clinical outcomes and biomechanical properties of the knee in response to upper partial fibulectomy and to probe into the biomechanical mechanism underlying the clinical benefits of upper partial fibulectomy for medial compartment knee osteoarthritis (KOA). A total of 29 patients with medial compartment KOA underwent upper partial fibulectomy. Visual analog scale (VAS) pain, the hospital for special surgery knee score (HSS), hip-knee-ankle (HKA) angle (measured in the frontal plane), and flexion/extension range of motion of the knee were assessed before and up to 6 months after surgery. Patients and 20 healthy controls were evaluated by 3D gait analysis and dynamic lower limb musculoskeletal analysis. Both VAS pain and HSS score were significantly improved (p < 0.001) one day after surgery and steadily improved during the subsequent 6 months. HKA angle improved (p = 0.025) immediately and remained stable by 3 months after surgery. The decreased overall peak KAM (decreased by 11.1%) and increased HKA angle (increased by 1.80 degrees from a more varus to more neutral alignment) of affected and operated side by 6 months after surgery were observed. Muscle activity of biceps femoris caput longum of affected and operated side increased immediately and was equivalent to healthy controls by 6 months after surgery (p = 0.007). This pilot study provides biomechanical evidence of benefit from partial upper fibulectomy and indicates a plausible rationale for the improvement in clinical symptoms. Long-term clinical outcomes and precise biomechanical mechanism of partial upper fibulectomy should be further investigated. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 9999:1-10, 2018.

Upper partial fibulectomy improves knee biomechanics and function and decreases knee pain of osteoarthritis: A pilot and biomechanical study.

To investigate the change in clinical outcomes and biomechanical properties of the knee in response to upper partial fibulectomy. Sixteen patients with medial compartment knee osteoarthritis (KOA) underwent upper partial fibulectomy. Visual analog scale (VAS) pain, the hospital for special surgery knee score (HSS), hip-knee-ankle (HKA) angle (measured in the frontal plane), and flexion/extension range of motion of the knee were assessed before and up to 6 months after surgery. Patients were evaluated for gait parameters and overall peak knee adduction moment (KAM). Patient-specific finite element knee models were developed to investigate changes in load in response to fibulectomy. Both VAS pain and HSS score were significantly improved (P < .001) one day after surgery and steadily improved during the subsequent 6 months. HKA angle improved (P = .006) immediately and remained stable by 3 months after surgery. A significant inverse relationship (R = -0.528, P = .012) between the overall peak KAM (decreased by 19.1%) and the HKA (increased by 1.24° from a more varus to more neutral alignment) angle was observed. The minor load supported by the fibula preoperatively was spread post-operatively over the cortical bone of the tibial shaft. The mean stress in the medial tibial plateau was significantly decreased (P < .001), with a portion of the stress transferred to the posterior-lateral region of the tibial plateau after upper partial fibulectomy. This pilot study provides objective 3D gait and plausible biomechanical evidence for the improvement in clinical symptoms from partial upper fibulectomy.

Ground reaction vector re-adjustment-the secret of success in treatment of medial compartment knee osteoarthritis by novel high fibular osteotomy.

High fibular osteotomy has been preliminarily proved to be an effective treatment of knee osteoarthritis by excising a segment of bone at the proximal part of fibula. This imaginative procedure is clinical validated by its instant and explicit knee pain resorption and eventually deformity correction. The rationale of this treatment is named non-uniform settlement of the tibial plateau and used to elucidate the cause of knee joint degeneration, but cannot illuminate the reason of prompt postoperative pain resorption faithfully. To assist in better understanding of this therapeutic method and raising alert to possible unexpected complications, we proposed a new theory to elucidate the pain relief mechanism.

Efficacy of arthroscopy combined with fibular osteotomy in treatment of medial knee osteoarthritis / 局解手术学杂志

Objective To observe the clinical efficacy of arthroscopy and fibula osteotomy in the treatment of medial knee osteoarthritis.Methods Thirty-six patients with medial knee osteoarthritis treated in our hospital from September 2014 to September 2016 were divided into two groups according to the acceptable surgical protocol.The control group was treated by fibula osteotomy,and the observation group received arthroscopy combined with fibula osteotomy.The clinical signs and symptoms,VAS and ISOA scores were evaluated and compared between the two groups.Results The control group of 18 cases,clinical recovery in 0 cases,markedly effective in 7 cases,effective in 8 cases,3 cases with no effect,the effective rate was 38.9％;observation group of 18 cases,3 cases clinically cured,effective in 10 cases,effective in 5 cases,the effective rate was 72.2％.The effective rate of observation group was better than that of the control group,the difference was signicant (P ＜ 0.05).VAS and ISOA in both groups were significantly improved after operation,the difference was signicant (P ＜ 0.05);VAS improvement in observation group was better than that in control group,the difference was signicant(P ＜ 0.05),ISOA score in observation group was significantly better than that in control group,the difference was signicant(P ＜0.01).The clinical signs and symptoms(pain and numbness,walking,living and working abilities,tenderness,straight leg raising test,knee and Achilles reflex,total score) in two groups were improved respectively compared with those before treatment,and the differences were statistically significant(P ＜ 0.05).The pain and numbness,walking,tenderness,straight leg raising test and total score in the observation group were significantly different from those in the control group(P ＜ 0.05).Conclusion The arthroscopy and fibula osteotomy is safe and feasible to treat patients of medial knee osteoarthritis with less traumatic,more effective and better functional recovery.

The effect of orthotic devices on knee adduction moment, pain and function in medial compartment knee osteoarthritis: a literature review.

Background Knee braces and foot orthoses are commonly used to improve knee adduction moment, pain and function in subjects with knee osteoarthritis (OA). However, no literature review has been performed to compare the effects of foot orthoses and knee braces in this group of patients. Purpose The aim of this review was to evaluate the effects of foot orthoses and knee braces on knee adduction moment, pain and function in individuals with knee OA. Study design Literature review. Method The search strategy was based on the Population Intervention Comparison Outcome method. A search was performed in PubMed, Science Direct, Google Scholar and ISI web of knowledge databases using the PRISMA method and based on selected keywords. Thirty-one related articles were selected for final evaluation. Results The results of the analysis of these studies demonstrated that orthotic devices reduce knee adduction moment and also improve pain and function in individuals with knee OA. Conclusion Foot orthoses may be more effective in improving pain and function in subjects with knee OA. Both knee braces and foot orthoses reduce the knee adduction moment in knee OA and consequently patients typically do not need to use knee braces for a long period of time. Also, foot orthoses and knee braces may be more effective for medial compartment knee OA patients due to the fact that this treatment helps improve pain and function. Implications for Rehabilitation Knee braces and foot orthoses are commonly used for improving knee adduction moment, pain and function in subjects with knee osteoarthritis (OA). Orthotic devices can reduce knee adduction moment, pain and improve function in knee OA. The combined use of a knee braces and foot orthoses can provide more improvement in knee adduction moment, reduced pain and increased function.