Self-reported and performance-based outcomes following medial patellofemoral ligament reconstruction indicate successful improvements in knee stability after surgery despite remaining limitations in knee function

Preoperative subjective assessment of disease-specific quality of life significantly influenced the likelihood of achieving the minimal clinically important difference after surgical stabilization for recurrent lateral patellar instability

PURPOSE

To evaluate which factors exert a predictive value for not reaching the minimal clinically important difference (MCID) in patients who underwent a tailored operative treatment for recurrent lateral patellar dislocation (RLPD).

METHODS

A total of 237 patients (male/female 71/166; 22.4 ± 6.8 years) were included. The Banff Patellofemoral Instability Instrument 2.0 (BPII 2.0) and subjective rating of knee function and pain (numeric analogue scale [NAS]; 0-10) were used to evaluate patients' outcomes from pre- to postoperatively. Gender, age at the time of surgery, body mass index (BMI), nicotine abuse, psychiatric diseases, cartilage status and pathoanatomic risk factors were evaluated as potential predictors for achieving the MCID using univariate logistic regression analysis.

RESULTS

The MCID for the BPII 2.0 was calculated at 9.5 points. Although the BPII 2.0 and NAS for knee function and pain improved significantly in the total cohort from pre- to postoperatively (all p < 0.001), 29 patients did not reach the MCID at the final follow-up. The analysis yielded that only the preoperative NAS for function and BPII 2.0 score values were significant predictors for reaching the MCID postoperatively. The optimal threshold was calculated at 7 (NAS function) and 65.2 points (BPII 2.0). Age at the time of surgery should be considered for patients with a preoperative BPII 2.0 score >62.5.

CONCLUSION

The probability of reaching BPII 2.0 MCID postoperatively depends only on the preoperative BPII 2.0 value and subjective rating of knee function, as well as age at the time of surgery for patients undergoing surgical treatment of RLPD. Here, presented results can assist clinicians in advising and presenting patients with potential outcomes following treatment for this often complex and multifactorial pathology.

LEVEL OF EVIDENCE

Level III.

Isolated Medial Patellofemoral Ligament Reconstruction Results in Lower Failure and Complication Rates Than Isolated Trochleoplasty and Tibial Tubercle Osteotomy: A Systematic Review

PURPOSE

To evaluate outcomes and complications of isolated medial patellofemoral ligament reconstruction (MPFLR), tibial tubercle osteotomy (TTO), and trochleoplasty for management of patellar instability.

METHODS

A query of Scopus, PubMed, Google Scholar, Cochrane CENTRAL Register of Controlled Trials, and the Cochrane Database of Systematic Reviews was performed in accordance with 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included studies reported clinical outcome data after isolated MPFLR, TTO, or trochleoplasty for patellar instability with a minimum 12-month follow-up. Meta-analysis and data aggregation was not performed.

RESULTS

Thirty-six studies (5 trochleoplasty, 14 TTO, and 18 MPFLR) consisting of 1,389 patients (114 trochleoplasty, 374 TTO, and 1,001 MPFLR) were included. Risk of bias was assessed with the Methodological Index for Non-Randomized Studies score, which ranged from 11 to 12 in trochleoplasty, 10 to 18 in TTO, and 8 to 18 in MPFLR studies. Patient-reported outcome measures, including Lysholm score (trochleoplasty: 51.1-71 to 71-95; TTO: 57-63.3 to 84-98; MPFLR: 37.4-59.1 to 74-92.5), Kujala score (trochleoplasty: 56-71 to 78-92; TTO: 48.6-68 to 78-92; MPFLR: 53.3-60 to 81.5-92), visual analog scale for pain (trochleoplasty: 52-25; TTO: 54-76 to 14-27; MPFLR: 29 to 17, out of 100), and Tegner score (TTO: 3-4 to 3-4; MPFLR: 2.5-6 to 4.9-5), improved after all surgeries. Failure rates ranged from 0% to 33.3% after MPFLR, 0% to 30.8% after TTO, and 5.3% to 40% after trochleoplasty. Complication rates ranged from 0% to 14.7% after MPFLR, 1.6% to 58.3% after TTO, and 8% to 26.3% after trochleoplasty.

CONCLUSIONS

Isolated MPFLR, TTO, or trochleoplasty may be effective treatment options for patellar stabilization. Although failure rates were highest after isolated trochleoplasty and complication rates were highest after TTO, these procedures are not interchangeable as each addresses a specific pathology.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II to IV studies.

Association between single leg hop tests and patient reported outcome measures and patellar instability in patients with recurrent patellar dislocations

Objectives

To assess the associations between the single leg hop tests at two premises; baseline and the change after 12 months, and change in patient reported outcome measures and persistent instability after 12 months in patients with recurrent lateral patellar dislocation (RLPD).

Methods

61 RLPD patients aged 12-30 with a mean (±SD) of 19.2 (±5.3) were assessed at baseline, and at 12 months after treatment with either active rehabilitation alone, or medial patellofemoral ligament reconstruction and active rehabilitation. Single leg hop for distance, triple hop for distance, crossover hop for distance and 6-metre timed hop were performed for both legs, and the Limb Symmetry Index (LSI) was calculated. Persistent patellar instability was self-reported as 'Yes' or 'No' at 12-month follow-up. Knee function in sport and recreational activities and knee-related quality of life were assessed at baseline and 12 months follow-up using the Knee injury and Osteoarthritis Outcome Score (KOOS).

Results

LSI for the baseline single leg hop for distance and the triple hop for distance was significantly associated with persistent patellar instability at 12 months follow-up with an OR of 0.94 (95% CI 0.88 to 0.99) and OR of 0.91 (95% CI 0.84 to 0.99), respectively. No other statistically significant associations were detected.

Conclusion

Individuals with higher LSI values for the single leg hop for distance and triple hop for distance conducted at baseline had lower odds for persistent patellar instability at 12 months follow-up. Clinicians can use results from these hop tests to assess the risk of future recurrent patellar instability prior to treatment.

Study design

Retrospective cohort study.

Trial registration number

NCT02263807.

Feasibility of return to sports assessment 6 months after patellar instability surgery

BACKGROUND

The evidence regarding the usefulness of assessment tools to support decisions of return-to-sport after surgery for patellar instability is scarce. The purpose of this study was therefore to explore the feasibility of functional tests assessing readiness for return-to-sport six months after patellar stabilizing surgery. However, there is little evidence on what a functional assessment should include to support these decisions following surgery for patellar instability. Therefore the purpose of this study was to explore the feasibility of functional tests assessing readiness for return-to-sport six months after patellar stabilizing surgery.

METHODS

In this cross-sectional study a prospective cohort of 78 patients were subjected to a range of return-to-sport readiness tests at six months after surgery for patellar instability with an "a la carte" approach. Lower Quarter Y-Balance Test (YBT-LQ), single-legged hop tests and isokinetic strength tests were performed. In addition, self-reported function was measured with the Banff Patellofemoral Instability Instrument 2.0 (BPII) and Norwich Patellar Instability score (NPI). Return-to-sport clearance criteria were defined as: ≤4 cm YBT-LQ anterior reach difference between legs, leg-symmetry-index (LSI) ≥ 95% in the YBT-LQ composite score, mean sum score LSI ≥ 85% of all single-leg hop tests and LSI ≥ 90% in isokinetic quadriceps strength.

RESULTS

Sixty-four patients (82%) were able to complete all functional tests, while only eleven (14%) patients were deemed ready for return-to-sport, passing all return-to-sport clearance criteria. Patients with bilateral problems demonstrated worse performance in the contralateral leg, which resulted in higher LSI scores compared to individuals with unilateral instability. A supplementary finding was that the extent of surgery (MPFL-R only versus combined surgery) did not predict and mainly did not affect self-reported function or functional performance at the follow-up.

CONCLUSION

The functional assessment used in the current study seems feasible to conduct at six months after patellar stabilizing surgery. However, current suggested clearance standards and the use of leg-symmetry-index seems inappropriate for patients with patellar instability. Therefore, further exploration of appropriate tests and return-to-sport clearance criteria is justified.

TRIAL REGISTRATION

clinicaltrial.gov, NCT05119088. Registered 12.11.2021 - Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT05119088 .

Patients' experiences of living with patellar instability before and after surgery: a qualitative interview study

OBJECTIVES

To explore the experience of living with patellar instability before and after surgery.

DESIGN

Qualitative individual semistructured interviews of patients with patellar instability using a four-step thematic cross-case analysis strategy (systematic text condensation).

SETTING

Two orthopaedic units within two large Hospitals in Norway.

PARTICIPANTS

A convenience sample of 15 participants, aged between 16 and 32 years, who had undergone surgery for patellar instability within the last 6-12 months.

RESULTS

Participants offered rich and detailed descriptions of the impact and lived experience of patellar instability, including fear of new dislocations, increased awareness of the knee and adaptations to avoidance behaviour in everyday life both before and after surgery. The four major themes that emerged from the data were: (1) fear of patella dislocations governs everyday life activities, (2) adaptation to avoidance behaviour, (3) feeling different, misunderstood and stigmatised affects self-esteem and (4) feeling stronger, but still not fully confident in the knee after surgery.

CONCLUSIONS

These findings offer insight into the experience of living with patellar instability. Patients reported that the instability had major impacts on their everyday life, affecting ability to participate in social life and physical activities both before and after surgery. This may imply that an increased attention towards cognitive interventions may be useful in the management of patellar instability.

TRIAL REGISTRATION NUMBER

NCT05119088.

Quality of life following medial patellofemoral ligament reconstruction combined with medial tibial tubercle transfer in patients with recurrent patellar dislocation: a retrospective comparative study

Background

Because the patients undergoing medial patellofemoral ligament reconstruction (MPFLr) combined with medial tibial tubercle transfer (TTT) procedure are usually young and active, the quality of life (QoL) is also an important prognostic factor for patients with recurrent patellar dislocation. Assessing QoL can provide more useful and accurate evidence for the effects of this procedure. This study aimed to evaluate QoL following MPFLr combined with TTT, compared with isolated MPFLr (iMPFLr).

Methods

Fifty-one patients who underwent iMPFLr + TTT and 48 patients who underwent iMPFLr were included. Clinical evaluation included QoL (EQ-5D-5L and EQ-5D VAS), functional outcomes (Kujala, Lysholm and Tegner activity scores), physical examinations (patellar apprehension test and range of motion) and redislocation rates. Radiological evaluation included patellar tilt angle and bisect offset. These preoperative and postoperative results were compared between groups at baseline and the final follow-up. The paired and independent t tests were used for the data following a normal distribution. Otherwise, the Wilcoxon and Mann–Whitney U tests were used to analyze the differences. Categorical variables were compared by chi-square or Fisher’s exact test.

Results

All of the QoL (EQ-5D-5L and EQ-5D VAS), clinical results and radiological outcomes significantly improved in both groups at the final follow-up, with no significant differences between groups. There was no significant difference in five dimensions of EQ-5D at the final follow-up, although percentages of people with problems of mobility and pain/discomfort were higher in the MPFLr + TTT group. Female patients had lower EQ-5D index and EQ-5D VAS compared with male patients in both groups at the final follow-up, but there was only a significant difference in the EQ-5D VAS.

Conclusions

Both MPFLr + TTT and iMPFLr groups obtained similar and satisfactory improvements in the QoL, clinical results and radiological outcomes, indicating that MPFLr combined with TTT is a safe and effective procedure, which can significantly improve the QoL for patients with recurrent patellar dislocation in cases of pathologically lateralized TT. However, female patients obtained lower QoL than males.

Mental and physical health-related quality of life in patients with recurrent patellar dislocations-a generic and disease-specific quality of life questionnaire assessment

Purpose

There is a paucity of quality of life (QoL) assessments in studies evaluating patients treated for recurrent lateral patellar dislocation (LPD). The primary aim of this study was to investigate whether mental well-being is impaired in patients with chronic (recurrent) LPD and, if so, to assess whether the mental health-related QoL dimension improves equivalently to the physical-related QoL dimension after successful surgical treatment.

Methods

Thirty-eight patients with recurrent LPD over a mean course of the disease of 4.7 ± 3.9 years (1—18 years) prior to surgery were included. Generic health-related QoL (HRQoL) (Short Form 36; SF-36) and disease-specific QoL (Banff Patella Instability Instrument 2.0; BPII 2.0) were assessed preoperatively and after a mean follow-up of 3.5 ± 0.8 years (2 – 5 years) postoperatively.

Results

Untreated LPD significantly impacted the physical dimension of patients’ generic HRQoL and their disease-specific QoL. When compared to age-equivalent normative data sets, the mental HRQoL dimension was not reduced prior to operative treatment but increased during the follow-up period. Surgical treatment normalized the physical dimension of patients’ generic HRQoL and significantly improved their disease-specific QoL. However, BPII 2.0 values remained reduced, albeit patellae were successfully stabilized.

Conclusion

The results of this study indicate that patients with recurrent LPD are generally in good mental health, although physical impairment is striking. Notwithstanding that surgery prevented further dislocations and normalized the generic HRQoL, the disease-specific QoL remained reduced as far as this can be interpreted without population-based data.

Level of evidence

Level IV; Retrospective case series.

Medial patellofemoral ligament reconstruction for recurrent patellar dislocation allows a good rate to return to sport

PURPOSE

Recurrent patellar dislocation is a frequent knee disorders in young, active patients. Medial patellofemoral ligament reconstruction (MPFLR) can restore knee stability and function, but the rate of return to sports is less clear. The aim of this study was to evaluate rate of return to sport following treatment of recurrent patellar dislocation with isolated MPFLR.

METHODS

Between 2011 and 2018, 113 patients with recurrent patellar dislocation were treated with isolated MPFLR at an academic center. Pre-injury sports participation and Tegner score, pre-operative subjective IKDC score, time to return to sports, and post-operative Tegner and subjective IKDC scores were collected, with a minimum of follow-up of 2 years.

RESULTS

One hundred and three patients (91%) were evaluated at a mean of 4.5 ± 2.5-year post-operative. 92 patients (89%) participated in sports prior to onset of patellar instability. At final follow-up, 84 of these 92 patients (91%) were able to return to sports. The mean time from surgery to return to sports was 10.4 ± 8.6 months (range: 2-48 months). 62 patients (67%) returned to the same (50 patients) or higher (12 patients) level. 22 patients (26%) returned at a lower level. 19 of these patients attributed this decreased participation to ongoing knee problems. The median Tegner score was noted to decrease from 5 pre-injury to 4 post-operatively (p = 0.02).

CONCLUSION

Isolated MPFL reconstruction allowed return to pre-injury sports in 91% of patients, with 67% of patients returning to the same or higher level than pre-injury. Mean time to return to sports was 10 months and post-operative Tegner score was noted to be modestly decreased from pre-injury level.

LEVEL OF EVIDENCE

IV.

Can the Eight Hop Test Be Measured with Sensors? A Systematic Review

Rehabilitation aims to increase the independence and physical function after injury, surgery, or other trauma, so that patients can recover to their previous ability as much as possible. To be able to measure the degree of recovery and impact of the treatment, various functional performance tests are used. The Eight Hop Test is a hop exercise that is directly linked to the rehabilitation of people suffering from tendon and ligament injuries on the lower limb. This paper presents a systematic review on the use of sensors for measuring functional movements during the execution of the Eight Hop Test, focusing primarily on the use of sensors, related diseases, and different methods implemented. Firstly, an automated search was performed on the publication databases: PubMed, Springer, ACM, IEEE Xplore, MDPI, and Elsevier. Secondly, the publications related to the Eight-Hop Test and sensors were filtered according to several search criteria and 15 papers were finally selected to be analyzed in detail. Our analysis found that the Eight Hop Test measurements can be performed with motion, force, and imaging sensors.

Increased tibial tubercle-trochlear groove and patellar height indicate a higher risk of recurrent patellar dislocation following medial reefing

PURPOSE

Identifying anatomical risk factors on recurrent dislocation after medial reefing is important for deciding surgical treatment. The present study aimed to retrospectively analyze the preoperative magnetic resonance imaging (MRI)-based parameters of patients treated with medial reefing and whether these parameters lead to a higher risk of recurrent dislocation.

METHODS

Fifty-five patients (18.6 ± 6.6 years) who underwent medial reefing after primary traumatic patellar dislocation (84% with medial patellofemoral ligament [MPFL] rupture) were included. Patients were followed up for at least 24 months postoperatively (3.8 ± 1.2 years) to assess the incidence of recurrent patellar dislocation. In patients without recurrent dislocation, the Kujala and subjective IKDC scores were assessed. Moreover, the tibial tubercle-trochlear groove (TT-TG), sulcus angle, patellar tilt, patellar shift, and lateral trochlea index (LTI) were measured. The patellar height was measured using the Caton-Dechamps (CDI), Blackburne-Peel (BPI), and Insall-Salvati index (ISI). The cohort was subclassified into two groups with and without recurrent dislocation. Differences between groups were analyzed with respect to the MRI parameters.

RESULTS

Forty percent had a pathological sulcus angle of > 145°, 7.2% had an LTI of < 11°, 47.3% had a patellar tilt of > 20°, and 36.4% had a TT-TG of ≥ 16 mm. Increased patellar height was observed in 34.5, 65.5, and 34.5% of the patients as per CDI, BPI, and ISI, respectively. Nineteen (34.5%) patients suffered from recurrent dislocation. Compared with patients without recurrent dislocation, those with recurrent dislocation had a significantly lower LTI (p = 0.0467). All other parameters were not significantly different between the groups. Risk factor analysis showed higher odds ratios (OR > 2), although not statistically significant, for MPFL rupture (OR 2.05 [95% confidence interval 0.38-11.03], LTI (6.6 [0.6-68.1]), TT-TG (2.9 [0.9-9.2]), and patellar height according to ISI (2.3 [0.7-7.5]) and CDI (2.3 [0.7-7.5])). Patients without recurrent dislocation had a Kujala score of 93.7 ± 12.1 (42-100) points and an IKDC score of 90.6 ± 11.7 (55.2-100) points.

CONCLUSION

Anatomical, MRI-based parameters should be considered before indicating medial reefing. A ruptured MPFL, an LTI < 11°, a TT-TG ≥ 16 mm, a patellar tilt > 20 mm, and an increased patellar height according to ISI and CDI were found to be associated, although not significantly, with a higher risk (OR > 2) of recurrent patellar dislocation after medial reefing. Thorough preoperative analysis is crucial to reduce the risk of recurrent dislocation in young patient cohorts.

LEVEL OF EVIDENCE

Level IV.

Return to Play After Medial Patellofemoral Ligament Reconstruction: A Systematic Review

BACKGROUND

Medial patellofemoral ligament (MPFL) reconstruction is being performed more frequently in athletes experiencing recurrent patellar instability.

PURPOSE/HYPOTHESIS

The purpose was to systematically review the evidence in the orthopaedic sports medicine literature to determine both the rate and timing of return to play after MPFL reconstruction and the rate of further patellar instability. Our hypothesis was that there would be a high rate of return to play after MPFL reconstruction.

STUDY DESIGN

Systematic review.

METHODS

A systematic literature search was performed based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, which utilized EMBASE, MEDLINE, and the Cochrane Library databases. Inclusion criteria for literature included clinical studies reporting on return to play after MPFL reconstruction. Rate of return to play, level of return, timing of return, rate of recurrent instability, and patient-reported outcomes were evaluated. Statistical analysis was performed using SPSS.

RESULTS

Our review found 27 studies including 1278 patients meeting our inclusion criteria. The majority of patients were women (58%), and the total group had a mean age of 22.0 years and a mean follow-up of 39.3 months. The overall rate of return to play was 85.1%, with 68.3% returning to the same level of play. The average time to return to play was 7.0 months postoperatively. The rate of recurrent instability events following reconstruction was 5.4%. There was an improvement in both mean visual analog scale, pain scores (preoperative: 4.3, postoperative: 1.6) and Tegner activity scores (preoperative: 4.8, postoperative: 5.5).

CONCLUSION

The overall rate of return to play was high after MPFL reconstruction for the treatment of recurrent patellar instability. However, a relatively high percentage of those patients were unable to return to their preoperative level of sport. Additionally, there was a moderate time taken to return to play, at approximately 7 months after the procedure.

Complex patellofemoral reconstruction leads to improved physical and sexual activity in female patients suffering from chronic patellofemoral instability

PURPOSE

To analyze postoperative physical and sexual activity as well as Quality of Life (QoL) after complex patellofemoral reconstructions in female patients suffering from chronic patellofemoral instability (PFI).

METHODS

Female patients aged > 18 years undergoing complex patellofemoral reconstruction for chronic PFI were included. Complex patellofemoral reconstruction was defined as medial patellofemoral ligament reconstruction (MPFL-R) combined with at least one major bony procedure (distal femoral osteotomy, high tibial osteotomy, and trochleoplasty). Outcome was evaluated retrospectively after a minimum follow-up of 12 months using Tegner activity scale, Banff Patellofemoral Instability Instrument 2.0 (BPII 2.0), EuroQol-5D-3L (EQ-5D-3L), EuroQol Visual analog scale (EQ-VAS), and a questionnaire about sexual activity.

RESULTS

A total of 34 females (mean age, 26 ± 5 years) with a mean follow-up of 45 ± 16 months were included. Seventy-seven percent had one major bony correction + MPFL-R and 24% had at least two major bony corrections + MPFL-R. The re-dislocation rate was 6%. Median Tegner activity scale improved from 3 (range 0-10) to 4 (range 2-6) (n.s.) and an improved activity level was observed in 49% of subjects. QoL scores showed an EQ-5D-3L Index Value of 0.89 ± 0.15, EQ-VAS of 80.3 ± 11.4, and BPII of 68.3 ± 19.1. Thirty-four percent of patients reported restrictions of sexual activities due to PFI preoperatively with an improved sexual function observed in 60% postoperatively due to less pain, improved mobility, and less apprehension. Postoperative return to sexual activity was 91%, whereof 19% reported current restrictions of sexual function because of pain and/or limited range of motion.

CONCLUSION

Despite the complexity and invasiveness of complex patellofemoral reconstruction, combined bony procedures and MPFL-R resulted in a low redislocation rate, improved physical activity and QoL comparable to values reported after isolated MPFL-R. Furthermore, sexual activity was improved in 60% of females with preoperative restrictions.

LEVEL OF EVIDENCE

IV.