Prognostic Factors for Return to Sport After High Tibial Osteotomy: A Directed Acyclic Graph Approach

Return to Duty in Military Servicemembers After High Tibial Osteotomy Not Associated With Preoperative Radiographic Parameters : A Retrospective Analysis

Background

Evidence on return to sports/work after high tibial osteotomy (HTO) is limited, especially in a young, high-demand population.

Purpose

To (1) identify whether preoperative knee pathology or intraoperative correction was associated with successful return to duty (RTD) and (2) assess whether postoperative complications and reoperation were associated with failure to RTD.

Study Design

Case series; Level of Evidence, 4.

Methods

We performed a retrospective cohort study of a consecutive series of patients in the Military Health System aged 18 to 55 years with medial compartment osteoarthritis who underwent HTO between 2003 and 2018. Concomitant meniscal and cartilage procedures were included, while cases with concomitant ligamentous procedures were excluded. The inclusion criteria were as follows: active-duty military status, minimum 2-year follow-up, preoperative knee radiographs, and pre- and postoperative long-leg alignment radiographs. Preoperative Kellgren-Lawrence grades and pre- and postoperative hip-knee-ankle angles were measured. The primary outcome was RTD. Failure was defined as knee-related medical separation from the military or conversion to total knee arthroplasty. The secondary outcome was reoperation.

Results

A total of 55 HTOs were performed in 50 patients who met the inclusion criteria, with a mean age of 39 years old (range, 22.8-55 years). The mean follow-up was 5 years (range, 2.1-10.7 years). Ten knees (18.2%) failed HTO (1 conversion to total knee arthroplasty, 9 medical separations), 15 additional knees (27.3%) had permanent activity restrictions, and 30 knees (54.5%) returned to duty without restrictions. Reoperation occurred in 36.4% of knees and was associated with medical separation (P = .039). Younger age was associated with medical separation (P = .003) and permanent restrictions (P = .006). Patients with a postoperative varus deformity of >5° were more likely to undergo medical separation (P = .023).

Conclusion

In a young, high-demand population, HTO succeeded in returning 54.5% of knees to full duty without restriction despite 36.4% of knees requiring reoperation. Residual varus deformity or reoperation was associated with lower RTD rates. No association was identified between RTD and preoperative osteoarthritis grading or deformity.

Knee Joint Line Obliquity With Adaptational Hip and Ankle Joint Orientation After Medial Open Wedge High Tibial Osteotomy

BACKGROUND

Time-dependent postoperative changes in knee joint line obliquity (KJLO) and subsequent adaptational changes in the hip and ankle joints have not been fully proven after medial open wedge high tibial osteotomy (MOWHTO).

PURPOSE

To investigate the serial postoperative changes in KJLO and subsequent adaptational changes in the hip and ankle joints over time after MOWHTO.

STUDY DESIGN

Case series, Level of evidence, 4.

METHODS

A total of 92 patients who underwent MOWHTO between April 2015 and December 2020 were evaluated. Radiographic parameters, including KJLO, ankle joint line obliquity (ALO), hip abduction angle (HAA), joint line convergence angle, weightbearing line ratio, and hip-knee-ankle angle, were analyzed in time sequence (preoperatively and 3, 6, 12, and 24 months postoperatively). Repeated-measures analysis of variance and post hoc analysis were used to demonstrate alterations and the statistical significance of KJLO and other related radiographic parameters over time.

RESULTS

The mean KJLO values were -1.9°, -2.1°, -2.7°, and -3.2° at 3, 6, 12, and 24 months postoperatively, respectively, indicating that there was consistent increase in valgus tilting of KJLO from 6 to 24 months (P < .001 for both 6-12 months and 12-24 months). ALO and HAA showed significant changes from 6 to 12 months (ALO, P < .001; HAA, P = .002), but not between 12 and 24 months (ALO: -3.0°, -2.7°, -1.9°, and -1.6°; HAA: -0.8°, -0.9°, -1.5°, and -1.8° at 3, 6, 12, and 24 months, respectively). The mean joint line convergence angle, weightbearing line ratio, and hip-knee-ankle angle did not change significantly from 3 months to 24 months postoperatively.

CONCLUSION

There was a consistent increase in valgus tilting of the postoperative KJLO from 6 to 24 months after MOWHTO. The adaptive ALO and HAA significantly changed between 6 and 12 months and were maintained until 24 months after MOWHTO. It is necessary to consider the adaptive change when hip or ankle surgery is planned within this period.

High tibial osteotomy versus unicompartmental knee arthroplasty for Kellgren-Lawrence grade 3-4 knee osteoarthritis in younger patients: comparable improvements in patient-reported outcomes, adjusted for osteoarthritis grade and sex

PURPOSE

Previous studies comparing high tibial osteotomy (HTO) with unicompartmental knee arthroplasty (UKA) have seldom accounted for differing patient characteristics between both groups. This study compared patient-reported outcomes (PROs) of HTO and UKA patients, adjusted for preoperative PROs, osteoarthritis grade and sex.

METHODS

A retrospective study was performed analysing prospectively collected PROs, namely the Oxford Knee Score (OKS) and pain/satisfaction scores, collected preoperatively and at 6 months, 12 months and 24 months postoperatively. Consecutive medial opening-wedge HTOs and medial UKAs from 2016-2019, with a preoperative Kellgren-Lawrence grade ≥ 3, aged 50-60 years, were included. Linear mixed model analyses, with the OKS over time as the primary outcome, were used.

RESULTS

We included 84 HTO patients (mean age 55.0 ± 3.0, 79% male, mean BMI 27.8 ± 3.4, 75% Kellgren-Lawrence grade 3) and 130 UKA patients (mean age 55.7 ± 2.8, 47% male, mean BMI 28.7 ± 4.0, 36% Kellgren-Lawrence grade 3). Response rates were ≥ 87% at all time points. Corrected for preoperative PROs, Kellgren-Lawrence grade and sex, the HTO group had a 2.5 (95% CI 1.0-4.0) points lower OKS over time than the UKA group (p = 0.001). The Numeric Rating Scale scores (NRS; 0-10) for pain at rest and during activity were higher (p < 0.01) in the HTO group. The EQ-5D-descriptive system (p < 0.01), NRS satisfaction (p < 0.01), anchor function and pain scores (p < 0.01) were lower over time in the HTO group.

CONCLUSION

UKA patients had better OKS scores, pain and satisfaction scores over time than HTO patients. However, the observed differences were below their established minimal clinically important differences. Therefore, from the patients' perspective, HTO did not appear to be inferior to UKA under the indications outlined in this study. Level of evidence Level IV.

Assessment of return to sport and functional outcomes following distal femoral, double level and high tibial osteotomies for active patients with symptomatic varus malalignment

PURPOSE

This study indicated the outcomes of three surgical techniques for the treatment of symptomatic unicompartmental knee osteoarthritis (UKOA) with varus malalignment in younger, active patients: distal femoral osteotomy (DFO), double-level osteotomy (DLO) and high tibial osteotomy (HTO). The outcomes measured included the return to sport, sport activity and functional scores.

METHODS

A total of 103 patients (19 DFO, 43 DLO, 41 HTO) were enrolled in the study and were divided into three groups based on their oriented deformity, each undergoing one of the three surgical techniques. All patients underwent pre- and post-operative evaluations including X-rays, physical exams and functional assessments.

RESULTS

All three surgical techniques were effective in treating UKOA with constitutional malalignment. The average time to return to sport was similar among the three groups (DFO: 6.4 ± 0.3 [5.8-7] months, DLO: 4.9 ± 0.2 [4.5-5.3] months, HTO: 5.6 ± 0.2 [5.2-6] months). The sport activity and functional scores improved significantly for all three groups, with no significant differences observed among the groups.

CONCLUSION

Various knee osteotomy procedures, DFO, DLO, and HTO, result in high RTS rates and quick RTS times with satisfactory functional scores. Despite pre- to post-operative improvements in sport activities following DFO and DLO, pre-symptom levels were not reached following all evaluated procedures.

LEVEL OF EVIDENCE

Retrospective case-control study, Level III.

Directed acyclic graphs in perioperative observational research-A systematic review and critique against best practice recommendations

The Directed Acyclic Graph (DAG) is a graph representing causal pathways for informing the conduct of an observational study. The use of DAGs allows transparent communication of a causal model between researchers and can prevent over-adjustment biases when conducting causal inference, permitting greater confidence and transparency in reported causal estimates. In the era of 'big data' and increasing number of observational studies, the role of the DAG is becoming more important. Recent best-practice guidance for constructing a DAG with reference to the literature has been published in the 'Evidence synthesis for constructing DAGs' (ESC-DAG) protocol. We aimed to assess adherence to these principles for DAGs constructed within perioperative literature. Following registration on the International Prospective Register of Systematic Reviews (PROSPERO) and with adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting framework for systematic reviews, we searched the Excerpta Medica dataBASE (Embase), the Medical Literature Analysis and Retrieval System Online (MEDLINE) and Cochrane databases for perioperative observational research incorporating a DAG. Nineteen studies were included in the final synthesis. No studies demonstrated any evidence of following the mapping stage of the protocol. Fifteen (79%) fulfilled over half of the translation and integration one stages of the protocol. Adherence with one stage did not guarantee fulfilment of the other. Two studies (11%) undertook the integration two stage. Unmeasured variables were handled inconsistently between studies. Only three (16%) studies included unmeasured variables within their DAG and acknowledged their implication within the main text. Overall, DAGs that were constructed for use in perioperative observational literature did not consistently adhere to best practice, potentially limiting the benefits of subsequent causal inference. Further work should focus on exploring reasons for this deviation and increasing methodological transparency around DAG construction.

Favorable rates of return to activity and work following lateral closing wedge distal femoral osteotomy for femoral-based symptomatic varus malalignment: an analysis at a mean 6-year follow-up

PURPOSE

To evaluate return to sport (RTS), work (RTW) and clinical outcomes following lateral closing wedge distal femoral osteotomy (LCW-DFO) for symptomatic femoral varus malalignment.

METHODS

Consecutive patients who underwent LCW-DFO for symptomatic varus malalignment between 12/2007 and 03/2018 were included. The International Knee Documentation Committee (IKDC) Score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lysholm score, Tegner Activity Scale, and visual analogue scale (VAS) for pain were collected preoperatively and at a minimum of 24 months postoperatively. RTS and RTW were assessed by questionnaire.

RESULTS

Thirty-two patients (mean age: 45.9 ± 12.3 years), who underwent LCW-DFO for femoral-based varus malalignment (6.4 ± 3.0°), were included at a mean follow-up of 72.7 ± 39.1 months. The patient collective significantly improved in IKDC (51.8 ± 12.3 to 61.8 ± 21.5, p = 0.010; 95% CI = 3-21), WOMAC (26.7 ± 17.6 to 12.5 ± 13.5; p < 0.001; 95% CI = 21-6) and Lysholm (46.5 ± 19.4 to 67.9 ± 22.8 points (p < 0.01; 95% CI = 9-31)) scores at final follow-up. The VAS for pain reduced significantly postoperatively (4.8 ± 2.3 points to 2.6 ± 2.3 points (p = 0.002; 95% CI = 0-3)). Following LCW-DFO, 96% of patients returned to sports at a mean of 5.3 ± 2.9 months. Yet, a shift to lower impact sports compared to one year preoperatively was observed, with patients participating in a significantly lower number of high-impact disciplines (p = 0.024) and fewer hours in high-impact sports (p = 0.034). Twenty-three out of 24 patients returned to work at a mean 11.4 ± 10.9 weeks, with 18 patients reporting a similar or superior working ability.

CONCLUSION

Undergoing isolated LCW-DFO for symptomatic femoral-based varus malalignment enabled the vast majority of patients to RTS and RTW along with a significant functional improvement at mid-term follow-up. However, patients' expectations have to be adequately managed regarding a limited probability to return to high-impact sports and work after surgery.

LEVEL OF EVIDENCE

Retrospective case series; Level IV.

Risk Factors Affecting Return to Sports and Patient-Reported Outcomes After Opening-Wedge High Tibial Osteotomy in Active Patients

Background:

Although opening-wedge high tibial osteotomy (OWHTO) is favored for active patients who expect to return to sports, there is still a lack of robust evidence for factors affecting their recovery.

Purpose:

To identify (1) risk factors leading to a decreased level of return to preoperative sports after OWHTO and (2) patient characteristics and intraoperative factors influencing patient-reported outcomes after return to sports.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

Included were 69 patients who underwent OWHTO and who expected to return to their preoperative level of sports, measured as a Tegner activity level ≥2. All included patients had a minimum of 1 year of follow-up data. Logistic regression analyses were performed to assess the effect of independent variables on the level of return to preoperative sports after surgery; the independent variables were age, sex, body mass index, preoperative Tegner score, preoperative Kellgren-Lawrence grade, preoperative percentage of mechanical axis (%MA), opening gap width, concomitant meniscal treatment, postoperative %MA, postoperative medial proximal tibial angle (MPTA), and postoperative posterior tibial slope. Univariate and multiple regression analyses were performed to assess for influencing factors on postoperative International Knee Documentation Committee (IKDC) subjective scores in patients who were able to return to sports.

Results:

Of the 69 patients, 51 (73.9%) returned to sports after OWHTO. High preoperative Tegner scores were statistically associated with a decrease in return to sports (odds ratio, 1.494; P = .033). Multiple regression analysis (n = 46 patients) identified that a higher postoperative MPTA was associated with a decreased IKDC subjective score after return to sports (r = –0.345; P = .019).

Conclusion:

Higher postoperative MPTA was associated with the worsening of patient-reported outcomes among those patients who did return to their preoperative sports after OWHTO. Also, participation in high-activity sports was confirmed to be a significant risk factor for a decreased rate of return to preoperative sports. These findings can support preoperative planning and intraoperative decision making, particularly for active patients.

Return to Sport and Work after Randomization for Knee Distraction versus High Tibial Osteotomy: Is There a Difference?

Knee joint distraction (KJD) is a novel technique for relatively young knee osteoarthritis (OA) patients. With KJD, an external distraction device creates temporary total absence of contact between cartilage surfaces, which results in pain relief and possibly limits the progression of knee OA. Recently, KJD showed similar clinical outcomes compared with high tibial osteotomy (HTO). Yet, no comparative data exist regarding return to sport (RTS) and return to work (RTW) after KJD. Therefore, our aim was to compare RTS and RTW between KJD and HTO. We performed a cross-sectional follow-up study in patients <65 years who previously participated in a randomized controlled trial comparing KJD and HTO. Out of 62 eligible patients, 55 patients responded and 51 completed the questionnaire (16 KJDs and 35 HTOs) at 5-year follow-up. The primary outcome measures were the percentages of RTS and RTW. Secondary outcome measures included time to RTS/RTW, and pre- and postoperative Tegner's (higher is more active), and Work Osteoarthritis or Joint-Replacement Questionnaire (WORQ) scores (higher is better work ability). Patients' baseline characteristics did not differ. Total 1 year after KJD, 79% returned to sport versus 80% after HTO (not significant [n.s.]). RTS <6 months was 73 and 75%, respectively (n.s.). RTW 1 year after KJD was 94 versus 97% after HTO (n.s.), and 91 versus 87% <6 months (n.s.). The median Tegner's score decreased from 5.0 to 3.5 after KJD, and from 5.0 to 3.0 after HTO (n.s.). The mean WORQ score improvement was higher after HTO (16 ± 16) than after KJD (6 ± 13; p = 0.04). Thus, no differences were found for sport and work participation between KJD and HTO in our small, though first ever, cohort. Overall, these findings may support further investigation into KJD as a possible joint-preserving option for challenging "young" knee OA patients. The level of evidence is III.

Editorial Commentary: Timely Surgery, Optimizing Perioperative Care, and Prospective Data Collection Are Next Steps to Improving Return to Sport and Work Outcomes After Knee Osteotomy

Knee osteotomy is a valuable treatment option for younger knee osteoarthritis patients. Improved surgical techniques, including double-level osteotomies to address femoral and tibial malalignment, have led to reappreciation of this joint-sparing alternative to knee arthroplasty. Yet, postoperative ability to resume sport and work at the desired level needs further improvement. We believe that timely surgery, optimized perioperative care, including evidence-based advice for resumption of activities, and prospective data collection are interesting next steps in this process.

Improved Clinical Outcome and High Rate of Return to Low-Impact Sport and Work After Knee Double Level Osteotomy for Bifocal Varus Malalignment

PURPOSE

To evaluate return to sport (RTS) and work (RTW), as well as clinical outcomes following double level osteotomy (DLO) via combined medial open wedge high tibial osteotomy and lateral closing wedge distal femoral osteotomy for bifocal symptomatic varus malalignment, and to compare these outcome parameters between patients undergoing a single surgery and those undergoing a two-stage procedure.

METHODS

Consecutive patients who underwent DLO for symptomatic varus malalignment between 12/2007 and 03/2018 were enrolled. Patients converted to arthroplasty (n = 3) during follow-up were excluded. Outcome measures included the International Knee Documentation Committee (IKDC) Score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lysholm score, Tegner Activity Scale, and visual analog scale (VAS) for pain, which were collected preoperatively and at a minimum of 24 months postoperatively. RTS and RTW were evaluated by questionnaire. Outcome measures were compared between DLO performed in a single- versus a two-stage surgery.

RESULTS

Thirty-two patients (mean age: 44.2 ± 12.6 years), who underwent DLO for varus malalignment (10.1° ± 2.9°) were included at a mean follow-up of 56.9 ± 35.3 months (range: 24-148). Compared to preoperatively, these patients significantly improved in IKDC (50.4 ± 13.9 to 66.1 ± 15.4; P < .001), WOMAC (29.7 ± 19.2 to 11.8 ± 13.5; P < .001) and Lysholm (53.6 ± 23.6 to 73.1 ± 23.6; P = .002) scores at final follow-up. For the WOMAC score, 78% of the patients included reached the minimally important clinical difference, along with a significant reduction of the VAS for pain (5.0 ± 3.0 to 2.5 ± 2.4; P < .001). Postoperatively, 96% of patients returned to sport after 7.7 ± 4.8 months, but at a lower frequency (P = .010) and to fewer disciplines (P = .005) with a shift to low-impact sports. 90% of the patients returned to work at a mean 5.9 ± 9.4 months, with 79% reporting a similar or superior working ability. Patients undergoing a two-stage procedure recovered to full physical working ability at a significantly longer duration, as compared to a single-stage procedure (9.8 ± 3.8 vs 9.0 ± 13.1 months; P = .047).

CONCLUSION

The majority of patients undergoing DLO for symptomatic varus malalignment, who were not converted to arthroplasty, experienced clinically significant functional improvement at mid-term follow-up. Return to sport and work rates in these patients were high; however, a shift to lower-impact sports disciplines was observed. Similar clinical outcomes can be expected when performing DLO in a single surgery or a two-stage procedure.

LEVEL OF EVIDENCE

Retrospective case series; Level IV.

Return to Sport and Work Following Distal Femoral Varus Osteotomy: A Systematic Review

Background: Distal femoral varus osteotomy (DFVO) is an effective surgical intervention for the management of symptomatic valgus malalignment of the knee. Because it preserves the native knee joint and its ligamentous stability, DFVO is preferred to total knee arthroplasty (TKA) in the young, active population. Purpose: We sought to assess return to work (RTW) and return to sport (RTS) rates following DFVO for valgus malalignment of the knee. Methods: For this systematic review, we searched EMBASE, MEDLINE, and Web of Science from inception through December 31, 2020. English language studies of all levels of evidence explicitly reporting on RTS and RTW rates following DFVO for valgus malalignment of the knee were eligible for inclusion. Results: Seven studies and 127 patients were included in our analysis. Mean age was 32.4 ± 8.8 years with men comprising 46.7% ± 22.3% of study populations. The mean RTS rate was 87.2% ± 10.7%, with a return to preoperative activity levels rate of 65.4% ± 26.8%. The mean RTW rate was 81.8% ± 23.3%, with a return to preoperative activity levels of 72.8% ± 18.1%. The mean reoperation rate was 35.6% ± 18.8% within a mean follow-up period of 5.5 ± 1.9 years. Conclusions: This systematic review of low-level studies found DFVO to be a safe and effective procedure for the management of genu valgum in young, active populations, with most patients returning to sport and/or work, although not all at their preoperative activity levels. A paucity of data surrounds RTS and RTW rates following DFVO. Future studies should explicitly report both return to activity rates and whether patients returned to their preoperative activity levels.

Patients return to sports and to work after successful treatment of septic arthritis following anterior cruciate ligament reconstruction

PURPOSE

To determine specific return to sports (RTS) and return to work (RTW) rates of patients with septic arthritis following anterior cruciate ligament reconstruction (ACLR), and to assess for factors associated with a diminished postoperative return to physical activity after successful eradication of the infection.

METHODS

In this study, patients who were treated for postoperative septic arthritis of the knee following anterior cruciate ligament reconstruction between 2006 and 2018 were evaluated at a minimum follow-up (FU) of 2 years. Patients' outcomes were retrospectively analyzed using standardized patient-reported outcome scores including the Lysholm score and the subjective IKDC score, as well as return to sports and return to work questionnaires to assess for the types, number, and frequency of sports performed pre- and postoperatively and to evaluate for potential occupational changes due to septic arthritis following ACLR. To assess for the signifiance of the graft at follow-up, outcomes were compared between patients with a functioning graft at FU and those without, as well as between patients with initial graft retention and those with graft removal and consecutive revision ACLR.

RESULTS

Out of 44 patients eligible for inclusion, 38 (86%) patients at a mean age of 36.2 ± 10.3 years were enrolled in this study. At a mean follow-up of 60.3 ± 39.9 months, the Lysholm score and the subjective IKDC score reached 80.0 ± 15.1 and 78.2 ± 16.6 points, respectively. The presence of a graft at FU yielded statistically superior results only on the IKDC score (p = 0.014). There were no statistically significant differences on the Lysholm score (n.s.) or on the IKDC score (n.s.) between patients with initial graft retention and those with initial removal who had undergone revision ACLR. All of the included 38 patients were able to return to sports at a median time of 8 (6-16) months after their last surgical intervention. Among patients who performed pivoting sports prior to their injury, 23 (62.2%) returned to at least one pivoting sport postoperatively. Overall, ten patients (26.3%) returned to all their previous sports at their previous frequency. The presence of a graft at FU resulted in a significantly higher RTS rate (p = 0.010). Comparing patients with initial graft retention and those with graft removal and consecutive revision ACLR, there was no statistically significant difference concerning the RTS rate (n.s.). Thirty-one patients (83.8%) were able to return to their previous work.

CONCLUSION

Successful eradication of septic arthritis following anterior cruciate ligament reconstruction allows for a postoperative return to sports and a return to work particularly among patients with ACL-sufficient knees. However, the patients' expectations should be managed carefully, as overall return rates at the pre-injury frequency are relatively low.

LEVEL OF EVIDENCE

IV.

Differences in the Demographics and Preferred Management of Knee Cartilage Injuries in Soccer Players Across FIFA Centers of Excellence

OBJECTIVE

We sought to report on the demographics and epidemiology of knee cartilage injuries and preferred management in soccer players, across FIFA Medical Centers of Excellence (FMCE).

DESIGN

A descriptive questionnaire focusing on characteristics of knee cartilage injuries and their management in soccer players during the 10-year period prior to the distribution of the questionnaire was sent to all FMCE around the world in September 2019 via an online platform. Voluntary responses from centers were processed and analyzed. Descriptive characteristics were reported using median and interquartile ranges (IQR) for continuous variables and frequencies and percentages (%) for discrete variables.

RESULTS

A total of 15 centers from 5 continents responded to the questionnaire and reported on a total of 4526 soccer players. Among centers, the median age was 27 years (IQR: 23-38), the median rate of male players was 75% (IQR: 68-90), and the median rate of professional players was 10% (IQR: 5-23). The most common reported etiology for cartilage injury was traumatic (median 40%, IQR: 13-73). The most common nonoperative treatment utilized was physical therapy (median 90%, IQR: 51%-100%) and the most common operative treatment utilized was bone marrow stimulation/micro-fracture (median 40%, IQR: 19-54%). The utilization of other cartilage restoration procedures varied across centers.

CONCLUSIONS

Our findings highlight different tendencies in the management of these injuries across FMCE and emphasize the need for collaborative efforts focusing on establishing consensus guidelines for the optimal management of these challenging injuries in soccer players.

Return to sports activity after opening wedge high tibial osteotomy in patients aged 70 years and older

BACKGROUND

The purpose of this study was to evaluate return to sports (RTS) after opening wedge high tibial osteotomy (OWHTO) in elderly patients and associated factors affecting RTS.

METHODS

Seventy-four patients (mean age 68 years) who underwent OWHTO were enrolled. Clinical outcomes were evaluated using the Knee Society Score (KSS). Patients were asked regarding types of sports activities and their levels of participation within preoperative 1 year and postoperative 1 year. Levels of participation in sports and recreational activities were examined using the Tegner activity scale. The outcomes were compared between two age groups (≥ 70 years vs. < 70 years).

RESULTS

Of the 74 patients overall, 59 participated in at least one sport preoperatively, and 55 returned to sports postoperatively (RTS 93%). The KSS knee score and function score were significantly improved after surgery in both age groups (P < 0.05), but no significant differences were found between the age groups. The Tegner activity scales for ≥ 70 years and < 70 years were 2.9 ± 1.1 and 4.0 ± 1.9 preoperatively (P < 0.01) and 2.7 ± 1.2 and 3.3 ± 1.4 postoperatively (P = 0.16), respectively. RTS was reported by 24 of 25 (96.0%) in the age < 70 years group and 31 of 34 (91.2%) in the age ≥ 70 years group. Majority of age ≥ 70 years participated in low-impact sports preoperatively and returned to the same impact level postoperatively.

CONCLUSIONS

The rate of RTS after OWHTO was high in patients aged 70 years and older with low-impact level. OWHTO is a preferred surgical option for elderly patients who desire RTS.

The difficulty of continuing sports activities after open-wedge high tibial osteotomy in patient with medial knee osteoarthritis: a retrospective case series at 2-year-minimum follow-up

Purpose

This study aimed to investigate the rate at which patients returned to sports after open wedge high tibial osteotomy and identify the continuity of sports activity post-operatively.

Methods

Thirty-five patients (40 knees) who underwent open-wedge high tibial osteotomy (OW-HTO) in medial knee osteoarthritis were included in this study. The mean age of the patients who underwent surgery was 55.1 ± 10.7 years, and the mean follow-up period was 41.0 ± 24.7 months. Clinical results and radiographic parameters calculated in standing whole-leg radiographs preoperatively, post-operatively, and at the final follow-up were evaluated.

Results

Thirty-one patients (88.6%) were able to return to preoperative sports activity; however, only 14 patients (40.0%) completely returned to preoperative sports activity levels. Of the 31 patients who returned to sports activity, 10 patients (32.3%) maintained post-operative sporting activity levels at the final follow-up. In radiographic parameters, the weight-bearing line ratio was considered loss of correction in the post-operative period leading to the final follow-up. Patients who completely returned to sports and maintained sporting activity levels at the final follow-up had significantly higher the Knee Injury and Osteoarthritis Outcome Score pain subscale values and lower visual analogue scale of knee pain at pre-surgery and final follow-up than other patients, including those who partially returned to sports.

Conclusions

The proportion of patients who returned to sports after OW-HTO and were able to participate in competitions at the same activity level as before surgery was low and insufficient.

Level of evidence

Retrospective case series, IV

Good Validity and High Internal Consistency of the Forgotten Joint Score-12 in Patients After Medial Opening Wedge High Tibial Osteotomy

BACKGROUND

The Forgotten Joint Score-12 (FJS-12) was originally developed to assess awareness of an artificial joint. Medial opening wedge high tibial osteotomy (MOWHTO), an alternative surgical method of knee replacement, is a joint-preservation surgery; therefore, joint awareness should be used to evaluate its clinical results. However, FJS-12 has not been validated as a tool to evaluate the postoperative results of MOWHTO. This study aimed to validate FJS-12 in MOWHTO.

METHODS

Patients with bilateral knee surgery, previous knee surgery, flexion contracture >15°, varus alignment >20°, and patients without plate removal surgery were excluded. Finally, 71 knees of 71 patients were analyzed, with a mean follow-up of 34.5 months. The FJS-12 score and Knee Injury and Osteoarthritis Outcome Score (KOOS) were obtained, and the floor and ceiling effect of each score was investigated. Cronbach's α was calculated to determine the internal consistency of FJS-12. Spearman's correlation coefficients between FJS-12 and KOOS were calculated to assess convergent validity.

RESULTS

There were ceiling effects in 3 KOOS subscales (symptoms [25.4%], pain [15.5%], and activities of daily living [25.4%]) but not in FJS-12 (8.5%). No floor effect was noted in any patient-reported outcome measures. The total Cronbach's α was 0.9457 in FJS-12. FJS-12 showed moderate-to-strong positive correlations with all KOOS subscales (r = 0.64-0.72).

CONCLUSION

FJS-12 showed a lower ceiling effect than KOOS and high internal consistency and convergent validity in patients following MOWHTO. With its low ceiling effect, FJS-12 was found to be useful for evaluating patients following MOWHTO.

Good clinical outcomes and return to sports after hybrid closed-wedge high tibial osteotomy

PURPOSE

This study aimed to investigate preoperative sports participation and postoperative clinical outcomes including a return to sports (RTS) after hybrid closed-wedge high tibial osteotomy (CWHTO) for medial compartment osteoarthritis of the knee. Characteristic of Hybrid CWHTO was defined as extra-articular lateral closed and medial open wedge osteotomy.

METHODS

The patients who underwent hybrid CWHTO from January 2016 to December 2018 were retrospectively reviewed and divided them into sports and non-sports groups. The preoperative demographic and radiographic characteristics were compared in both groups. And the clinical outcomes including the Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS), Lysholm score, University of California at Los Angeles (UCLA) activity score, and RTS in the sports group were also investigated. Statistical analysis was performed for comparisons among the preoperative factors between the two groups. Influence of sports impact and bone union of fibular osteotomy was also statistically investigated for RTS.

RESULTS

Of the 161 knees (129 patients; 46 males, 83 females), 20 knees (16 patients; 13 males, 3 females; 12.3%) belonged to sports group. Although there were no significant differences regarding the age and radiographic parameters, there were significant differences in the body mass index and proportion of males between both groups. The JOA, VAS, Lysholm, and UCLA activity scores significantly improved after surgery. RTS was 80% at a mean duration of 7.2 ± 3.1 months. RTS in the high-impact sports group was significantly lower than that in the low-impact sports group (high-impact 60% vs. low-impact 100%, p = 0.043). There was no significant difference in RTS regarding bone union after fibular osteotomy.

CONCLUSION

The clinical outcomes including RTS were satisfactory in patients with hybrid CWHTO.

LEVEL OF EVIDENCE

IV.

Patient Expectations and Satisfaction After Medial Opening Wedge High Tibial Osteotomy

BACKGROUND

The objective of this study is to assess preoperative patient expectations of medial opening wedge high tibial osteotomy (MOWHTO) and related postoperative fulfillment, to increase understanding of associated factors of postoperative satisfaction.

METHODS

One hundred fifteen patients who underwent MOWHTO were enrolled. Patients' expectations were measured using the Hospital for Special Surgery-Knee Replacement Expectations Survey. Fulfillment of expectations and satisfaction was evaluated using the Hospital for Special Surgery Knee Replacement Fulfillment of Expectations Survey and a 5-point Likert scale at 2 years, postoperatively. The discrepancies between preoperative expectation and postoperative fulfillment score were also assessed. Preoperative and postoperative patient-reported outcomes were evaluated using Western Ontario and McMaster Universities Arthritis Index (WOMAC) score. Univariate and multivariate analyses were performed to model predictions for satisfaction.

RESULTS

The most expected items were "pain relief," "walking ability," and "perform daily activities." The top 3 items with the biggest discrepancies between expectation and fulfillment scores were "kneeling," "squatting," and "pain relief." Ninety patients (78.3%) were satisfied and 25 (21.7%) were dissatisfied at 2 years postoperative. Multivariate logistic regressions showed that patient expectations did not affect satisfaction. Small discrepancies between expectation and fulfillment scores (odds ratio [OR] 105.304, 95% confidence interval 20.974-528.714, P < .001), high postoperative fulfillment scores (OR 1.198, 95% CI 1.110-1.293, P < .001), and low postoperative Western Ontario and McMaster Universities Arthritis Index total scores (OR 0.932, 95% CI 0.894-0.971, P < .001) were significantly associated with patient satisfaction.

CONCLUSION

The small discrepancy between preoperative expectations and postoperative fulfillment of expectations was a major contributor to patients' satisfaction following MOWHTO.

Opening wedge high tibial osteotomy allows better outcomes than unicompartmental knee arthroplasty in patients expecting to return to impact sports

PURPOSE

Prior studies have compared unicompartmental knee arthroplasty (UKA) with high tibial osteotomy (HTO) suggesting that both procedures had good functional outcomes. But none had established the superiority of one of the two procedures for patients with high expectation including return to impact sport. The aim of this study was to compare functional outcomes and ability to return to impact sport of active patients defined with a pre-arthritis University of California and Los Angeles activity (UCLA) score > 8, after UKA or HTO procedures.

METHODS

A retrospective review of patients with a pre-arthritis UCLA score > 8 operated between January 2014 and September 2017 has identified 91 patients with open-wedge HTO and 117 patients with UKA. A matching process based on age (± 3 years) and gender allowed to include 50 patients in each group for comparative analysis. Patient reported outcomes included Knee Osteoarthritis Outcomes Score (KOOS), UCLA Score, Knee Society Score (KSS) and time to return to sport or previous professional activities at 3, 6, 12 and 24 months following surgery.

RESULTS

Mean time to return to sport activities or previous professional activities were significantly lower for the HTO group than for UKA group [respectively, 4.9 ± 2.2 months for HTO group vs 5.8 ± 6.2 months for UKA group (p = 0.006) and 3 ± 3 months for HTO group vs 4 ± 3 months for UKA group (p = 0.006)]. At 24-month follow-up, UCLA score, KOOS Sports Sub-score and KSS activity score were significantly higher for HTO group than for UKA group (Δ: 2 CI 95% (1.3-2.5 points) p < 0.0001, (Δ: 10.9 CI 95% (2.9-18.9 points) p = 0.04 and Δ: 7.8 CI 95% (2.4-13.4 points) p = 0.006, respectively) and 31 patients (62%) were practicing impact sport in the HTO group versus 14 (28%) in the UKA group (odd-ratio 4.2 CI 95% (1.8-9.7) p < 0.0001).

CONCLUSION

HTO offers statistically significant quicker return to sport activities and previous professional activities with a higher rate of patients able to practice impact activity (62% for HTO vs 28% for UKA) and better sports related functional scores at two years after surgery compared to UKA.

LEVEL OF EVIDENCE

III retrospective case-control study.

Preoperative Medial Meniscal Extrusion Is Associated With Patient-Reported Outcomes After Medial Opening Wedge High Tibial Osteotomy

BACKGROUND

Although the medial compartment continues to sustain some loading after medial opening wedge high tibial osteotomy (MOWHTO) in varus-deformed knees, no studies have examined the relationship between medial meniscal extrusion (MME) and patient-reported outcome measures after MOWHTO.

PURPOSE

To examine whether compartmental baseline MME was associated with patient-reported outcome measures after MOWHTO.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

This retrospective study was composed of 149 MOWHTOs in 147 patients with clinical and radiological assessments. Patients were grouped according to severity of MME in the medial compartment at the time of surgery. MME was categorized into 4 groups according to MOAKS (MRI [magnetic resonance imaging] Osteoarthritis Knee Score) criteria and relative value of MME. We compared preoperative characteristics, including Kellgren-Lawrence (KL) grading scale, meniscal tear pattern, and postoperative Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscores. Associations between extent of MME and WOMAC subscores at postoperative 1 and 2 years were assessed with generalized linear models.

RESULTS

Pattern of meniscal tear (P < .05) and KL grade (P < .05) were associated with MME. Patients with KL grades 3 and 4 at the time of surgery had significantly greater MME than those with KL grade 2 (P < .05). When patients were divided into 4 groups according to MOAKS criteria at the time of surgery, there were significant differences in WOMAC pain scores among groups at 1 and 2 years after the operation (all P < .05). The WOMAC function score also differed among groups at postoperative 1 year (P < .05) but not postoperative 2 years (P > .05). When patients were divided into 4 groups according to relative MME at the time surgery, the WOMAC pain score differed significantly among groups at postoperative 1 and 2 years (all P < .05). Analysis of WOMAC pain score as the dependent variable in multivariate analyses revealed that severity of absolute and relative MME and KL grade were independent predictors of worse WOMAC pain score at postoperative 1 and 2 years (all P < .05).

CONCLUSION

Greater preoperative MME at the time of surgery was associated with inferior patient-reported outcomes, especially pain, in patients with MOWHTO at 1 and 2 years after surgery.

Predicting the knee adduction moment after high tibial osteotomy in patients with medial knee osteoarthritis using dynamic simulations

BACKGROUND

High tibial osteotomy (HTO) is a surgical treatment for knee osteoarthritis, which alters the load distribution in the tibiofemoral joint. To date, all surgical planning methods are based on radiographs, which do not consider the loading characteristics during ambulation. This study aimed to develop and validate a simulation tool for predicting the knee adduction moment (KAM) expected after a HTO using the patient pre-operative gait analysis data and dynamic simulations.

METHODS

Ten patients selected for a HTO underwent a gait analysis before surgery. Pre-operative gait data along with the planned correction angle were used for simulation of the KAM expected after leg realignment. After surgery, the same procedures of gait analysis were performed and post-operative KAM was compared to the simulation results.

RESULTS

Significant reductions of the KAM were observed after surgery. During gait at 1.2 m/s, means of the 1st peak KAM were 3.19 ± 1.03 (standard deviation), 1.21 ± 0.80 and 1.21 ± 0.71% BW × Ht for the conditions pre-operative, post-operative and simulation, respectively. Mean root-mean-square error for the KAM was 0.45% BW × Ht (range: 0.23-0.78% BW × Ht) and Lin's concordance coefficient for the 1st peak KAM was 0.813. An individual analysis showed high agreement for several patients and lower agreement for others. Possible changes in gait pattern after surgery may explain this variability.

CONCLUSION

A novel approach for surgical planning based on dynamic loading of the knee during ambulation is presented. The simulation tool is based on patient-specific gait characteristics and may improve the surgical planning procedures used to date.