Laurie A. Hiemstra

A Randomized Clinical Trial Comparing Open and Arthroscopic Stabilization for Recurrent Traumatic Anterior Shoulder Instability Two-Year Follow-up with Disease-Specific Quality-of-Life Outcomes

BACKGROUND The literature comparing open and arthroscopic repair for glenohumeral instability is conflicting. We performed a prospective, expertise-based, randomized clinical trial to compare open shoulder stabilization with arthroscopic shoulder stabilization by measuring quality-of-life outcomes and recurrence rates at two years among patients treated for traumatic anterior shoulder instability. METHODS Computer-generated, variable-block-size, concealed randomization allocated 196 patients to either the open-repair group (n = 98) or the arthroscopic-repair group (n = 98). An expertise-based randomization design was employed to avoid a differential bias in terms of physician experience. Outcomes were measured at baseline, at three and six months postoperatively, and at one and two years postoperatively with use of the Western Ontario Shoulder Instability Index (WOSI) and the American Shoulder and Elbow Surgeons (ASES) functional outcome scale. Recurrent instability was also analyzed. RESULTS There were no significant differences in outcome scores at baseline. At two years, seventy-nine patients in the open group and eighty-three patients in the arthroscopic group were available for follow-up. There was no significant difference in mean WOSI scores between the groups; the mean WOSI score (and standard deviation) for the open group was 85.2 ± 20.4 (95% confidence interval [CI] = 80.5 to 89.8), and for the arthroscopic group, 81.9 ± 19.8 (95% CI = 77.4 to 86.4); p = 0.31. There was also no significant difference in mean ASES scores: 91.4 ± 12.7 (95% CI = 88.5 to 94.4) for the open group and 88.2 ± 15.9 (95% CI = 84.6 to 91.8) for the arthroscopic group; p = 0.17. Recurrence rates at two years were significantly different: 11% in the open group and 23% in the arthroscopic group (p = 0.05). Recurrent instability was more likely in patients with a preoperative Hill-Sachs lesion and in male patients who were twenty-five years old and younger. There was no significant difference in shoulder motion between the groups at two years. CONCLUSIONS There was no difference between open and arthroscopic repair in terms of patient quality of life. Open repair resulted in a significantly lower risk of recurrence. Secondary outcome data from this trial suggest that open surgical repair may be recommended to reduce the risk of recurrent instability in younger male patients with a Hill-Sachs lesion.

Shoulder Strength after Open versus Arthroscopic Stabilization

Background With current techniques, the main difference between arthroscopic and open shoulder stabilization is the violation of the subscapularis tendon. No studies have looked at strength differences of internal and external rotation between these groups. Hypothesis Internal rotation strength deficits will exist in patients having undergone an open shoulder stabilization procedure compared with an arthroscopic one. Study Design Piggy-back randomized controlled trial; Level of evidence, 1. Methods Forty-eight patients (38 men, 10 women), average age, 30.6 years (range, 18–59 years), were randomized to either open (n = 24) or arthroscopic (n = 24) shoulder stabilization. Rehabilitation protocols were standardized. At a mean follow-up of 19.4 months (range, 12–36 months) from surgery, patients underwent isokinetic strength testing (concentric and eccentric peak moments at 60 deg/s and 180 deg/s). Measurements were body-mass normalized. Primary outcome was internal rotation strength at 60 deg/s. Results There were no significant differences between groups with respect to age, gender, or operative limb. There were no statistical differences between operative groups for the primary outcome of internal concentric strength at 60 deg/s (mean difference, 0.011 N·m/kg; 95% confidence interval, −0.043 to 0.066; P = .677) or secondary strength measures. When compared with the contralateral limb, strength deficits existed for both surgical groups for both internal and external rotation. Regression analysis demonstrated that arm dominance is a factor in strength deficits. Conclusion The results of this trial suggest there are no side-to-side isokinetic strength deficits between patients having an open stabilization using a subscapularis splitting approach versus arthroscopic stabilization for anterior traumatic shoulder instability at 1 year after surgery. Strength deficits exist in both groups when compared with the contralateral limb.

Knee Immobilization for Pain Control After a Hamstring Tendon Anterior Cruciate Ligament Reconstruction A Randomized Clinical Trial

Background This study will attempt to evaluate the efficacy of knee immobilization on patient pain levels after an anterior cruciate ligament reconstruction. Hypothesis There is no difference in visual analog scale pain scores 2 days after anterior cruciate ligament reconstruction between patients who wear a knee immobilizer and those who do not wear a knee immobilizer. Study Design Randomized clinical trial; Level of evidence, 1. Methods Patients aged 18 to 40 years who met study inclusion criteria were eligible. Patients meeting intraoperative inclusion critiera were randomized (immobilizer or no immobilizer) after wound closure. The immobilizer used was a soft, unhinged brace with Velcro® straps. Preoperative, intraoperative, and postoperative protocols were standardized. The primary outcome was patient self-assessed pain using a 0-to-100-mm visual analog scale at day 2 after surgery. Secondary outcomes included pain and analgesic use in the first 14 days after surgery, complications, and range of motion (approximately 3 weeks postoperatively). A sample size estimate was calculated and resulted in the need for 44 patients per group. Results A total of 102 patients were enrolled; 88 patients were randomized, and 14 were excluded intraoperatively. There was no difference in mean visual analog scale pain scores at 2 days after surgery between immobilized and nonimmobilized patients (32.6 and 35.2, respectively; P = .59; difference, —2.6; 95% confidence interval, —12.2 to 6.9). There were no differences between groups in medication consumed, range of motion, or complications. Pain and analgesic use were the same for both groups at 7 and 14 days postoperatively. Conclusion No differences in pain or any of the secondary outcomes were detected between immobilized and nonimmobilized patients at any point during the first 14 days after anterior cruciate ligament reconstruction.

Hip strength following hamstring tendon anterior cruciate ligament reconstruction.

Objective:The objective of this study was to determine whether there is alteration in resultant joint moment of the hip extensors and adductors after hamstring anterior cruciate ligament (ACL) reconstruction. Design:Cross-sectional outcome analysis. Setting:University sport medicine center. Subjects:Fifteen subjects more than 1 year after ACL reconstruction with semitendinosus and gracilis tendons were compared with 15 matched controls with no knee injury. Interventions:Strength testing of the hip extensors and hip adductors of both limbs. Main Outcome Measurements:Isokinetic (50°/s and 150°/s) hip extensor strength test and isometric (15° and 30°) hip adductor strength test. Results:Hip extensors increase in strength after hamstring ACL reconstruction, evening out normal side-to-side strength differences. Hip adductor strength deficits of up to 43% are demonstrated in the ACL reconstructed subjects compared with controls. Conclusions:The identification of hip adductor strength deficits after hamstring harvest for ACL reconstruction may have important implications for both graft harvest site selection as well as postoperative rehabilitation protocols. Given the known existence of knee strength deficits after ACL reconstruction, increases in isovelocity hip extensor strength may contribute to increased lower limb strength imbalances. This may have implications for the ability of the lower limb muscles to protect the ACL graft.

Initial Validity and Reliability of the Banff Patella Instability Instrument

Background: Patellofemoral instability is a well-recognized problem, but there are currently no published patient-reported quality of life outcome measures that are disease specific for the treatment of this population. Purpose: To establish the content validity, initial construct validity, and initial reliability of the Banff Patella Instability Instrument (BPII). Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: The content of the BPII was validated using a modified 3-stage Ebel procedure and analysis of floor and ceiling effects. As a measure of internal consistency, the Cronbach α was utilized to assess how reliably the 32 items of the questionnaire measured a similar construct. Test-retest reliability of the BPII was calculated using an intraclass correlation coefficient (ICC). Construct validity was evaluated on 150 questionnaires completed by patients with a confirmed diagnosis of patellofemoral instability. A one-way between-group analysis of variance was employed to determine if the BPII was able to differentiate between patients presenting at the initial orthopaedic consultation relative to patients presenting at 6 months and 12 months postoperatively. Results: Content validity was clearly established as each item in the BPII achieved a minimum of 83.3% agreement (range, 83.3%-100%) for relevance among the expert panelists. The average agreement was 96.9%; 24 items achieved 100% agreement. There was no evidence of floor or ceiling effects. Reliability (internal consistency) of the BPII was established at the initial orthopaedic consultation (α = .91), 6 months postoperatively (α = .97), and 12 months postoperatively (α = .97). Test-retest analysis resulted in an ICC of 0.98 between tests. Construct validity was established as there was a statistically significant difference in BPII scores at the initial orthopaedic consultation and 6-month and 12-month postoperative appointments (F2,146 = 75.62; P < .001). Conclusion: The BPII demonstrates content validity, strong initial reliability, and a statistically significant level of construct validity in patients with patellofemoral instability. This population includes patients with recurrent patellofemoral instability as well as surgically stabilized patients.

Effect of Trochlear Dysplasia on Outcomes After Isolated Soft Tissue Stabilization for Patellar Instability

Background: Trochlear dysplasia is a well-described risk factor for patellofemoral instability. Despite its clear association with the incidence of patellar instability, it is unclear whether the presence of high-grade trochlear dysplasia influences clinical outcome after patellofemoral stabilization. Purpose: To determine whether isolated proximal soft tissue stabilization for patellofemoral instability is as successful in patients with high-grade dysplasia compared with low-grade or no dysplasia, as measured by disease-specific quality-of-life and pain scores. Study Design: Case series; Level of evidence, 4. Methods: A total of 277 patellofemoral stabilization procedures were performed during the study period. An isolated stabilization was performed in 233 patients, and 203 of these patients (87%) had adequate lateral radiographs and complete Banff Patella Instability Instrument (BPII) scores available for assessment. Of these, 152 patients underwent a medial patellofemoral ligament reconstruction (MPFL-R) and 51 patients received a medial patellofemoral ligament imbrication (MPFL-I). There were 21 patients with no trochlear dysplasia, 89 patients with low-grade dysplasia (Dejour type A), and 93 patients with high-grade dysplasia (Dejour types B-D). An independent-samples t test was used to determine the difference between the pre- and postoperative BPII scores. A Spearman rho correlation was calculated between 3 trochlear dysplasia groups and the BPII scores at a mean 24 months after patellofemoral stabilization. An independent-samples t test was used to assess the influence of trochlear bump size on outcomes by stratifying data and assessing for a relationship to BPII scores. Results: The independent-samples t test demonstrated statistically significant improvements in pre- to postoperative BPII scores for both groups. The MPFL-R group improved from a mean BPII score of 24.36 to 65.16 (P < .001), and the MPFL-I group improved from a mean of 28.92 to 73.45 (P < .01). For the MPFL-R patient cohort, the Spearman rho correlation demonstrated a significant relationship between postoperative BPII scores and presence of a trochlear bump and degree of dysplasia (P ≤ .05). Overall, a trochlear bump of ≥5 mm was associated with lower postoperative BPII scores (t(193) = 2.65, η2 = 0.04). Conclusion: This research has established a statistically significant correlation between trochlear dysplasia and disease-specific outcomes after MPFL-R surgery. Overall, there was evidence of significant improvement in disease-specific quality-of-life scores after patellofemoral stabilization surgery. This study is the largest cohort reported to date and therefore adds substantially to the evidence that trochlear dysplasia is a significant risk factor for and predictor of outcome among patients with patellofemoral instability.

Anterior Knee Pain in the Athlete

Given that the patellofemoral joint is one of the most highly loaded in the human body, the high prevalence of anterior knee pain (AKP) in athletes is unsurprising. Athletes with AKP present a significant diagnostic and therapeutic challenge. A clear understanding of the etiology of patellofemoral pain in this population is essential in guiding a focused history and physical examination, and achieving an appropriate diagnosis and treatment approach. This clinical review provides an assessment framework and a guide for neuromuscular function testing, and an overview of the causes and treatments of AKP in this challenging patient population.

Concurrent Validation of the Banff Patella Instability Instrument to the Norwich Patellar Instability Score and the Kujala Score in Patients With Patellofemoral Instability.

Background: The Banff Patella Instability Instrument (BPII) is a disease-specific, patient-reported, quality-of-life outcome measure designed to assess patients with patellofemoral instability. The iterative assessment of the validity, reliability, and responsiveness of a health-related patient-reported outcome measure is vital to the development of a high-quality evaluation tool. Purpose: To assess the concurrent validity of the BPII to the Norwich Patellar Instability (NPI) score and the Kujala score. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 74 patients with a confirmed diagnosis of recurrent patellofemoral instability completed the BPII, NPI, and Kujala scores at the initial orthopaedic consultation. A Pearson r correlation coefficient was computed to determine the relationship between each of these patient-reported outcomes. Results: There were statistically significant correlations between the BPII and the NPI score (r = −0.53; P < .001) as well as the BPII and the Kujala score (r = 0.50; P < .001). Conclusion: This study demonstrated a moderately strong correlation of the BPII to other outcome measures used to evaluate patients with patellofemoral instability. This study adds further validity to the BPII in accordance with the COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) guidelines.

Medial Patellofemoral Ligament Reconstruction Femoral Tunnel Accuracy: Relationship to Disease-Specific Quality of Life

Background: Medial patellofemoral ligament (MPFL) reconstruction is a procedure aimed to reestablish the checkrein to lateral patellar translation in patients with symptomatic patellofemoral instability. Correct femoral tunnel position is thought to be crucial to successful MPFL reconstruction, but the accuracy of this statement in terms of patient outcomes has not been tested. Purpose: To assess the accuracy of femoral tunnel placement in an MPFL reconstruction cohort and to determine the correlation between tunnel accuracy and a validated disease-specific, patient-reported quality-of-life outcome measure. Study Design: Case series; Level of evidence, 4. Methods: Between June 2008 and February 2014, a total of 206 subjects underwent an MPFL reconstruction. Lateral radiographs were measured to determine the accuracy of the femoral tunnel by measuring the distance from the center of the femoral tunnel to the Schöttle point. Banff Patella Instability Instrument (BPII) scores were collected a mean 24 months postoperatively. Results: A total of 155 (79.5%) subjects had adequate postoperative lateral radiographs and complete BPII scores. The mean duration of follow-up (±SD) was 24.4 ± 8.2 months (range, 12-74 months). Measurement from the center of the femoral tunnel to the Schöttle point resulted in 143 (92.3%) tunnels being categorized as “good” or “ideal.” There were 8 failures in the cohort, none of which occurred in malpositioned tunnels. The mean distance from the center of the MPFL tunnel to the center of the Schöttle point was 5.9 ± 4.2 mm (range, 0.5-25.9 mm). The mean postoperative BPII score was 65.2 ± 22.5 (range, 9.2-100). Pearson r correlation demonstrated no statistically significant relationship between accuracy of femoral tunnel position and BPII score (r = –0.08; 95% CI, –0.24 to 0.08). Conclusion: There was no evidence of a correlation between the accuracy of MPFL reconstruction femoral tunnel in relation to the Schöttle point and disease-specific quality-of-life scores. Graft failure was not related to femoral tunnel placement. The patellofemoral instability population is complex, and patients present with multiple risk factors that, in addition to the accuracy of femoral tunnel position, contribute to quality of life and warrant further investigation.

Factor Analysis and Item Reduction of the Banff Patella Instability Instrument (BPII) Introduction of BPII 2.0

Background: Clinical management of patellofemoral (PF) instability is a challenge, particularly considering the number of variables that should be taken into consideration for treatment. Quality of life is an important measure to consider with this patient population. Purpose: To factor analyze and reduce the total number of items in the Banff Patella Instability Instrument (BPII). Subsequent to the factor analysis, the new, item-reduced BPII 2.0 was tested for validity, reliability, and responsiveness. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Quality of life was measured for PF instability patients (N = 223) through use of the original BPII at their initial consultation. Data from the BPII scores were used in a principal components analysis (PCA) to factor analyze and reduce the total number of items in the original BPII, to create a revised BPII 2.0. The BPII 2.0 underwent content validation (Cronbach alpha, patient interviews, and grade-level checking), construct validation (analysis of variance comparing the initial visit and the 6-, 12-, and 24-month postoperative visits, eta-square), convergent validation (Pearson r correlation to the original BPII), responsiveness testing (eta-square, anchor-based distribution testing), and reliability testing (intraclass correlation coefficient [ICC]). Results: The BPII was successfully reduced from 32 to 23 items with excellent Cronbach alpha values in the new BPII 2.0: initial visit = 0.91; 6-month postoperative visit = 0.96; 12-month postoperative visit = 0.97; and 24-month postoperative visit = 0.76. Grade-level reading for all items was assessed as below grade 12. The BPII 2.0 was able to discriminate between all time periods with significant differences between groups (P < .05). Eta-square was 0.40, demonstrating a medium to large effect size. The BPII significantly correlated with the BPII 2.0 (0.82, 0.90, 0.90, and 0.94 at the initial visit and 6-, 12-, and 24-month postoperative visits, respectively), providing evidence of convergent validity. A significant correlation was found between the 7-point scale and 24-month postoperative BPII 2.0 scores, a sign of anchor-based responsiveness. ICC (2,k) was 0.97, indicating strong reliability. Conclusion: The BPII 2.0 is valid, reliable, and responsive for assessment of patients with PF instability, both surgically and nonsurgically treated.