Ten-year clinical and magnetic resonance imaging evaluation after repair of isolated subscapularis tears

The impact of supraspinatus tear on subscapularis muscle atrophy and fatty infiltration

BACKGROUND

Aimed to report the prevalence and predisposing factors affecting subscapularis muscle atrophy and fatty infiltration (MAFI) in patients without a subscapularis tear, and to analyze the effect of this condition on surgical outcomes.

METHODS

Between 2020 and 2022, 153 patients (mean age 58.1 ± 10.2 years; 84 men and 69 women) who underwent repair of posterosuperior cuff tears, with no subscapularis tears identified during arthroscopy were retrospectively analyzed. Baseline characteristics, preoperative and follow-up (6 months) magnetic resonance imaging findings, arthroscopic findings, and clinical outcomes (>1 year) were recorded.

RESULTS

The prevalence of subscapularis MAFI (Goutallier grade 1 or 2) was 73.9% (113/153), of which the prevalence of Goutallier grade 2 was 23.5% (36/153). From multivariable logistic regression analysis, female sex (odds ratio [OR], 5.6; 95% CI, 1.7-18.6; P=0.005), older age (OR, 1.1; 95% CI, 1.0-1.1; P=0.052), advanced supraspinatus MAFI by Goutallier grade (OR, 3.2; 95% CI, 1.5-6.9; P=0.004), and synovitis (OR, 2.8; 95% CI, 1.1-7.9; P=0.030) were identified as independent predisposing factors for subscapularis MAFI. However, patients with preoperative subscapularis MAFI exhibited similar final range of motion, pain and function, and belly press strength compared to those without preoperative subscapularis MAFI.

CONCLUSIONS

Subscapularis MAFI is frequently observed conditions even in the absence of subscapularis tears, and this condition could be affected by supraspinatus MAFI, female sex, older age, and synovitis. However, because subscapularis MAFI does not affect the surgical outcome, surgeons need not be concerned about this condition when repairing posterosuperior rotator cuff tear. Level of evidence: IV.

Clinical and Structural Results Following Arthroscopic and Open Repair of Isolated Subscapularis Tears

Objective: With advances in techniques, arthroscopic repair of isolated subscapularis tendon tears has become increasingly popular in recent years. The aim of this study was to analyze the clinical and structural results of arthroscopic repair versus the gold standard of open repair. It is a prospective cohort study with a control group; evidence level III. Methods: In a prospective study performed at two centers, 18 patients with an isolated subscapularis tear were treated with arthroscopic repair (ARG) and 16 patients with open repair (ORG) using a uniform single-row suture anchor repair technique in both groups. The subscapularis function was assessed using specific clinical tests (belly-press and lift-off tests), strength testing and shoulder function with the use of the Constant-Murley score (CMS). Standardized magnetic resonance imaging (MRI) was used to evaluate the postoperative subscapularis muscle-tendon status. Results: At a minimum follow-up of 48 months, the CMS increased from a mean of 54 points preoperatively to a mean of 86 points postoperatively in the ARG (p < 0.01) and from 50 points to 85 points postoperatively in the ORG (p < 0.01). Specific subscapularis tests (belly-press test and lift-off test) were significantly improved from the preoperative to the postoperative status in both repair groups (p < 0.05). Despite a subscapularis tendon healing rate of over 90% on MRI scans in both repair groups, the incomplete correction of specific muscle tests was a frequent postoperative finding. Conclusions: Arthroscopic repair of isolated subscapularis tears achieved equivalent clinical and structural results compared to the gold standard of open repair.

The High Resistance Loop (H-Loop) Technique for Arthroscopic Repair of Subscapularis

The subscapularis tendon is more challenging and riskier to repair than the posterior upper rotator cuff. The knotless anchor suture in subscapularis repair simplified the repair process and had an excellent postoperative effect. We describe a new knotless anchor stitching method, the H-Loop technique. The simplicity and efficiency of the technique make it particularly suitable for small subscapular tendon tears.

Arthroscopic repair for isolated subscapularis tear: successful functional outcomes and high tendon healing rate can be expected nine years after surgery

BACKGROUND

Literature describing outcomes and integrity after isolated subscapularis (SSC) tendon repair is emerging but remains limited to a few small case series with short-term follow-up. The aim of this study was to evaluate the long-term clinical outcomes and repair integrity in patients who underwent arthroscopic repair of isolated SSC tears.

METHODS

A retrospective study was conducted with the following inclusion criteria: (1) primary and elective shoulder arthroscopy for isolated SSC repair, (2) type III (a full-thickness tear in the upper two-thirds of the tendon) or IV (a complete tear without tendon retraction) SSC tear according to the Lafosse classification, and (3) a minimum 24-month follow-up. Preoperatively, the range of motion (ROM) and the Constant-Murley score (CMS) and at follow-up, the ROM, the University of California-Los Angeles (UCLA) Shoulder Rating Scale, the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, and the CMS were evaluated; an ultrasonographic assessment of tendon healing was performed according to the Sugaya classification.

RESULTS

The final sample consisted of 45 patients with an average age of 55 ± 9 years. After a mean follow-up time of 107 ± 54 months, the mean UCLA and DASH scores were 8.7 ± 1.3 and 42.2 ± 6.4, respectively. ROM and CMS showed statistically significant improvements (all P < .001). Before surgery, the mean CMS was 49% that of sex- and age-matched healthy individuals, and all patients showed a CMS lower than the normative data. At the final follow-up visit, the mean CMS was 94.2% that of sex- and age-matched healthy individuals, and no patients showed CMS of 30 or less. The mean increase in the CMS was 41.4 ± 9.8 points (range, 23-60 points). The ultrasonographic assessment showed SSC tendon healing in 39 (86.7%) cases; tendon retear was recorded in 5 (13.3%) cases. All scores directly correlated with the healing of the tendon. A higher postoperative DASH score was associated with male sex (P = .039, β = 5.538) and a longer follow-up period (P = .044, β = 0.001). The postoperative CMS (P < .001) and UCLA scores (P = .001) were significantly higher in patients younger than 60 years of age at surgery than in older individuals.

CONCLUSION

Arthroscopic repair of isolated SSC tears achieves excellent clinical and functional results at a mean of 9 years postoperatively, with a satisfactory healing rate. Better functional outcomes correlate with SSC tendon integrity and were observed in male patients and in those younger than 60 years at surgery.

Determining minimal clinically important difference and patient-acceptable symptom state after arthroscopic isolated subscapularis repair

Background

Minimal Clinically Important Difference (MCID) and Patient-Acceptable Symptomatic State (PASS) have emerged as patient-based treatment assessments. However, these have not been investigated in patients undergoing arthroscopic isolated subscapularis repair (AISR). The primary purpose of this study was to determine the MCID and PASS for commonly used patient-reported outcomes in individuals who underwent AISR. The secondary purpose was to assess potential associations between preoperative and intraoperative patient characteristics and the MCID and PASS.

Methods

A retrospective analysis was conducted on prospectively collected data for patients who underwent primary AISR between 2011 and 2021 at a single institution, with minimum 2-year postoperative follow-up. Functional outcomes were assessed using the American Shoulder and Elbow Surgeons (ASES) score, Subjective Shoulder Value (SSV), and Visual Analog Scale (VAS) pain scale. The MCID was determined using the distribution-based method, while PASS was evaluated using area under the curve analysis. To investigate the relationship between preoperative variables and the achievement of MCID and PASS thresholds, Pearson and Spearman coefficient analyses were employed for continuous and noncontinuous variables, respectively.

Results

A total of 77 patients with a mean follow-up of 58.1 months were included in the study. The calculated MCID values for VAS pain, ASES, and SSV were 1.2, 10.2, and 13.2, respectively. The PASS values for VAS pain, ASES, and SSV were 2.1, 68.8, and 68, respectively. There was no significant correlation between tear characteristics and the likelihood of achieving a MCID or PASS. Female sex, worker's compensation status, baseline VAS pain score, and baseline ASES score, exhibited weak negative correlations for achieving PASS for VAS pain and ASES.

Conclusion

This study defined the MCID and PASS values for commonly used outcome measures at short-term follow-up in patients undergoing AISR. Tear characteristics do not appear to impact the ability to achieve a MCID or PASS after AISR. Female sex, worker's compensation claim, and low baseline functional scores have weak negative correlations with the achievement of PASS for VAS pain and ASES scores.

Clinical Outcomes and Tendon Healing After Arthroscopic Isolated Subscapularis Tendon Repair: Results at Midterm Follow-up

Background

Few studies have reported clinical outcomes and tendon healing rates after arthroscopic isolated subscapularis (SSC) repair (AISR).

Purpose/Hypothesis

The primary purpose of this study was to evaluate clinical outcomes and tendon healing after AISR. It was hypothesized that AISR would result in satisfactory clinical outcomes along with a high rate of tendon healing at the midterm follow-up. The secondary purpose was to assess the influence of tear size and muscle atrophy on SSC tendon healing and patient-reported outcomes. It was hypothesized that both would be negatively correlated with healing but would have no effect on clinical outcomes .

Study Design

Case series; Level of evidence, 4.

Methods

A retrospective analysis was conducted on prospectively collected data for 77 patients who underwent primary AISR between 2011 and 2021 at a single institution, with a minimum 2-year postoperative follow-up for all patients. Functional outcomes were assessed using the American Shoulder and Elbow Surgeons (ASES) score, the Subjective Shoulder Value (SSV), and the visual analog scale for pain. Repair techniques and concomitant procedures were also collected. SSC tendon healing was evaluated via ultrasound at the final follow-up. Linear regression analysis was performed to determine factors affecting SSC healing.

Results

The mean follow-up was 58.1 ± 3.3 months. ASES scores significantly improved from 41.5 to 81.6, and the SSV improved from 38.2 to 80.5 (P < .01 for both). Among the 40 patients (51.9%) who underwent postoperative ultrasound, 87.5% showed complete tendon healing. There were no significant differences in outcome scores between healed and unhealed tendons. Increased muscle atrophy and larger tears were correlated with failure of SSC healing (β = -0.285 [P = .015] and β = -0.157 [P = .045], respectively).

Conclusion

Improved clinical outcomes and an overall high rate of tendon healing were seen at the midterm follow-up after AISR. Smaller tear sizes with less muscle atrophy were correlated with improved tendon healing. However, even when the tendon incompletely healed, the procedure improved functional outcomes.

Arthroscopic Repair of Large Subscapularis Tear Over the First Facet

BACKGROUND

Long-term studies on arthroscopic repair of large subscapularis (SSC) tears over the first facet with or without supraspinatus (SSP) tear are limited.

PURPOSE

To assess the structural and clinical outcomes of arthroscopic repair of large SSC tears using magnetic resonance imaging (MRI) and identify the factors related to SSC retear and poor outcomes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This study involved 109 patients (84.0 ± 36.2 months of follow-up) who underwent arthroscopic repair of large SSC tears (Yoo and Rhee classification type III [n = 81] or IV [n = 28]) between 2011 and 2019. All patients underwent MRI at 6.1 ± 0.4 months after surgery, and 79 of 109 patients (72.5%) were followed up over 7 years. Clinical outcomes (active range of motion, functional scores, and belly press strength) and final poor clinical outcomes (reoperation, osteoarthritic change, and poor clinical outcome) were recorded. SSP tear size, rotator cuff atrophy and fatty infiltration (Goutallier classification), SSC tendon integrity (intact, intermediate, definite tear), and SSP tendon integrity (Sugaya classification) were evaluated by MRI.

RESULTS

The overall SSC retear rate was 8.3% (9/109) (type III, 2/81 [2.5%]; type IV, 7/28 [25.0%]; P < .001). SSC Goutallier grade 4 showed a higher retear rate than grade 3 (7/33 [21.2%] vs 2/33 [6.1%]; P = .149). A large SSP tear (in millimeters) (odds ratio [OR], 1.5; P = .003), SSC Goutallier grade 4 (OR, 10.8; P = .047), and SSP Goutallier grade 3 or 4 (OR, 0.02; P = .013) were independent factors for SSC retear. Clinical outcomes, except for external rotation, were poorer in patients with SSC retear than in those without retear. Final poor clinical outcomes were observed in 27 of 79 patients (34.2%); female sex (OR, 7.7; P = .007), SSC retear (OR, 8.2; P = .025), and SSP retear (OR, 4.7; P = .031) were independent factors.

CONCLUSION

Arthroscopic repair of large SSC tears has shown promising structural outcomes for type III tears but not type IV tears. SSC retear was affected by SSC atrophy, as well as SSP tear size and atrophy. Approximately one-third of the final poor clinical outcomes could be predicted, and SSC retear, SSP retear, and female sex were associated with long-term poor clinical outcomes, underscoring the importance of carefully selecting patients for arthroscopic repair of large SSC tears.

Long Head of the Biceps Pediculated Autograft Augmentation of Arthroscopic Subscapularis Repair

Subscapularis (SSc) repairs are not free of failure and continues to pose a challenging problem. Although various biological and structural augmentation methods are available for the posterosuperior rotator cuff, few options have been explored for the anterior one. In the Technical Note, we describe an all-arthroscopic technique in which we use the long head of the biceps tendon (LHBT) as a pediculated autograft to reinforce an SSc repair. After SSc repair and LHBT tenodesis, the intra-articular portion of the LHBT is placed on the upper part of the SSc tendon at the rotator interval. Repurposing the otherwise-discarded tendon brings several biological and mechanical advantages at a lower cost without donor-site morbidity.

Correlation between preoperative clinical examination and intraoperatively found subscapularis tendon tear

PURPOSE

Analyze the diagnostic value for subscapularis (SSC) tendon tears, their correlation between pain and strength on clinical tests, and compare them with intraoperative arthroscopic findings to prove their diagnostic value.

METHODS

110 consecutive patients undergoing arthroscopic rotator cuff repair were reviewed and allocated to isolated SSC (n = 39) and combined anterosuperior tendon tear (n = 71) groups and analyzed. Preoperative clinical testing included belly press (BPT), bear hug (BHT), lift-off (LOT), palm-up (PUT), and Jobe test (JT). All tests were performed in two categories: pain (in 4 categories: 0, 5, 10, and 15) and strength (from 0 to 5). The tendon tears were intraoperatively reviewed and classified.

RESULTS

Mean age was 59 years (SD 10). The sensitivity of the BHT was 88.2% and 74.5% for BPT, while specificity was only 41.9% for BHT and 45% for BPT. Sensitivity of JT was 90.5% and 87.5% for PUT, while specificity was only 41% for JT and 28.2% for PUT. A low positive correlation for an intraoperative SSC lesion and the strength of BPT (Spearman rank correlation  - 0.425; p value < 0.0001) and the strength of BHT ( - 0.362; p value = 0.001) could be found. With linear regression analysis estimated by ordinary least squares, a correlation between BPT strength and surgical grade of SSC lesion (- 0.528; 95% CI, - 0.923 to - 0.133; pvalue < 0.01) was found.

CONCLUSION

The BHT showed a higher sensitivity for a SSC lesion, while the BPT had a higher correlation between preoperative testing, most notably internal rotation strength, and intraoperative surgical grade of the SSC tendon lesion.

LEVEL OF EVIDENCE

Level II, Prospective cohort study for Diagnostic tests.

Arthroscopic Repair of Isolated Subscapularis Tears Show Clinical and Structural Outcome Better for Small Tears Than Larger Tears

Purpose

To retrospectively investigate the mid-term outcomes after arthroscopic repair of isolated subscapularis tears with a relatively large number of patients and to compare them by tear size.

Methods

Medical records were reviewed for patients who underwent arthroscopic rotator cuff repair between 2010 and 2017 at our institute. The inclusion criterion was isolated subscapularis tears that underwent arthroscopic rotator cuff repair. The exclusion criteria were (1) previous rotator cuff surgery, (2) lack of imaging studies or clinical evaluation data, (3) neuromuscular diseases, and (4) <2-year follow-up. Range of motion, American Shoulder and Elbow Society score, and bear-hug or belly-press test were assessed pre- and postoperatively. Repair integrity was evaluated with magnetic resonance imaging at postoperative1 year. The clinical and imaging study outcomes were compared between smaller (Lafosse types 1-3) and larger (types 4 and 5) tears.

Results

The subjects included 38 males and 8 females with a mean age of 59 years (range, 25-77 years). The mean follow-up was 36 months (range, 24-96 months). There were 13 type 1, 10 type 2, 12 type 3, 6 type 4, and 5 type 5 shoulders. Postoperative American Shoulder and Elbow Society scores were significantly better in smaller tears than larger tears: 93 ± 8 and 75 ± 14, respectively (P = .003). Smaller tears showed better postoperative internal rotation than larger tears (P = .004). Significant decrease of positive bear-hug or belly-press test was observed in smaller tears (preoperative, 25; postoperative, 11; P < .001), but there was no significant improvement in larger tears (preoperative, 11; postoperative, 9). The retear rate was significantly greater in larger tears (64%) than smaller tears (6%, P < .001).

Conclusions

The clinical and structural outcomes after arthroscopic repair of isolated subscapularis tears were better in smaller tears than larger tears with a mid-term follow-up. Larger tears showed high retear rates with poorer improvement in active range of internal rotation and subscapularis strength.

Level of Evidence

Level III, retrospective, comparative study.

Identifying key factors associated with subscapularis tendon tears and developing a risk prediction model to assist diagnosis

Background

There are still some challenges in diagnosing subscapularis (SSC) tendon tears as accurately as posterosuperior rotator cuff tears on MRI. The omission of SSC tendon tear can lead to muscle atrophy, fatty infiltration, and increased tearing accompanied by aggravated shoulder pain and loss of function. An effective non-invasive evaluation tool will be beneficial to early identification and intervention. The study aims to identify sensitive predictors associated with SSC tendon tears and develop a risk prediction model to assist in diagnosis.

Methods

Data on 660 patients who received shoulder arthroscopic surgery with preoperative shoulder MRI were collected retrospectively. Of these, patients with SSC tendon tears were defined as the SSC tear group, and patients with intact SSC tendon were enrolled in the non-SSC tear group. Logistic regression analysis was used to identify the key predictors of SSC tendon tears which were then incorporated into the nomogram.

Results

Among 22 candidate factors, five independent factors including coracohumeral distance (CHD, oblique sagittal plane) (OR, 0.75; 95%CI, [0.67–0.84]), fluid accumulation (Y-face) (OR, 2.29; 95%CI, [1.20–4.38]), long head of biceps tendon (LHB) dislocation/subluxation (OR, 3.62; 95%CI, [1.96–6.68]), number of posterosuperior (PS) rotator cuff tears (OR, 5.36; 95%CI, [3.12–9.22]), and MRI diagnosis (based on direct signs) (OR, 1.88; 95%CI, [1.06–3.32]) were identified as key predictors associated with SSC tendon tears. Incorporating these predictors, the nomogram achieved a good C index with a good agreement on the risk estimation of calibration plots. Higher total points of the nomogram were associated with a greater risk of SSC tendon tears.

Conclusion

When evaluating the severity of SSC tendon injury, the combination of reliable predictors can improve the sensitivity and diagnostic performance of MRI. This model provides an individualized probability of risk prediction, which is convenient for clinicians to identify patients at high risk for SSC tendon tears to avoid missed diagnosis.

Current concepts review in the management of subscapularis tears

Subscapularis (SSc) is the prime internal rotator of shoulder. It is the most powerful rotator cuff muscle, maintaining the anterior force couple of shoulder. The tears in SSc as any other rotator cuff muscles might result from a traumatic event or more commonly from intrinsic degeneration. With the advent and widespread use of shoulder arthroscopy, SSc tears, which were once considered as "forgotten or hidden lesions" are now being increasingly recognized. Isolated SSc tears are relatively rare. They occur in combinations. Clinically internal rotation can be near normal because of the compensation provided by other internal rotators. It is not uncommon for patients with SSc tear to be normal on routine physical examination. The Bear Hug test (BHT) has high sensitivity and accuracy in the diagnosis of SSc tear. The combined use of BHT with Belly Press Test has been found optimal for diagnosis. US is an accurate and reliable method for diagnosing SSc tears and outperformed MRI in diagnosing partial-thickness SSc tears. The MRI is currently the most advanced imaging available for diagnosis. The specificity is up to 100%. However, the sensitivity is between 36 and 40%. The earliest classification system for SSc tears was by Fox et al. The commonly used classification is by Lafosse et al. The recent system by Yoo et al. is based on the insertion of SSc. The comma sign is gaining importance not only in arthroscopic diagnosis but also in MRI identification and repair of SSc. The mode of management is mainly arthroscopic. The techniques of repair of SSc are continuously progressing. However, there is no clear consensus on the double vs single-row repairs, biceps tendon management, and the role of coracoplasty. Future research must focus on these areas. Reserve shoulder arthroplasty is reserved for salvage in older age groups. Tendon transfers are performed in young active individuals with irreparable tears.

Atrophy patterns in isolated subscapularis lesions

BACKGROUND

While supraspinatus atrophy can be described according to the system of Zanetti or Thomazeau there is still a lack of characterization of isolated subscapularis muscle atrophy. The aim of this study was to describe patterns of muscle atrophy following repair of isolated subscapularis (SSC) tendon.

METHODS

Forty-nine control shoulder MRI scans, without rotator cuff pathology, atrophy or fatty infiltration, were prospectively evaluated and subscapularis diameters as well as cross sectional areas (complete and upper half) were assessed in a standardized oblique sagittal plane. Calculation of the ratio between the upper half of the cross sectional area (CSA) and the total CSA was performed. Eleven MRI scans of patients with subscapularis atrophy following isolated subscapularis tendon tears were analysed and cross sectional area ratio (upper half /total) determined. To guarantee reliable measurement of the CSA and its ratio, bony landmarks were also defined. All parameters were statistically compared for inter-rater reliability, reproducibility and capacity to quantify subscapularis atrophy.

RESULTS

The mean age in the control group was 49.7 years (± 15.0). The mean cross sectional area (CSA) was 2367.0 mm² (± 741.4) for the complete subscapularis muscle and 1048.2 mm² (± 313.3) for the upper half, giving a mean ratio of 0.446 (± 0.046). In the subscapularis repair group the mean age was 56.7 years (± 9.3). With a mean cross sectional area of 1554.7 mm² (± 419.9) for the complete and of 422.9 mm² (± 173.6) for the upper half of the subscapularis muscle, giving a mean CSA ratio of 0.269 (± 0.065) which was seen to be significantly lower than that of the control group (p < 0.05).

CONCLUSION

Analysis of typical atrophy patterns of the subscapularis muscle demonstrates that the CSA ratio represents a reliable and reproducible assessment tool in quantifying subscapularis atrophy. We propose the classification of subscapularis atrophy as Stage I (mild atrophy) in case of reduction of the cross sectional area ratio < 0.4, Stage II (moderate atrophy) in case of < 0.35 and Stage III (severe atrophy) if < 0.3.