Rotator cuff pathology is the main cause of shoulder pain and dysfunction in older adults. When a rotator cuff tear involves the subscapularis tendon, the symptoms are usually more severe and the prognosis after surgery must be guarded. Isolated subscapularis tears represent 18% of all rotator cuff tears and arthroscopic repair is a good alternative primary treatment. However, when the tendon is deemed irreparable, tendon transfers are the only option for younger or high-functioning patients. The aim of this review is to describe the indications, biomechanical principles, and outcomes which have been reported for tendon transfers, which are available for the treatment of irreparable subscapularis tears.

The best tendon to be transferred remains controversial. Pectoralis major transfer was described more than 30 years ago to treat patients with failed surgery for instability of the shoulder. It has subsequently been used extensively to manage irreparable subscapularis tendon tears in many clinical settings. Although pectoralis major reproduces the position and orientation of the subscapularis in the coronal plane, its position in the axial plane – anterior to the rib cage – is clearly different and does not allow it to function as an ideal transfer. Consistent relief of pain and moderate recovery of strength and function have been reported following the use of this transfer. In an attempt to improve on these results, latissimus dorsi tendon transfer was proposed as an alternative and the technique has evolved from an open to an arthroscopic procedure. Satisfactory relief of pain and improvements in functional shoulder scores have recently been reported following its use. Both pectoralis minor and upper trapezius transfers have also been used in these patients, but the outcomes that have been reported do not support their widespread use.

Cite this article: Bone Joint J 2024;106-B(9):970–977.

Aims. Favourable short-term outcomes have been reported following latissimus dorsi tendon transfer for patients with an irreparable subscapularis (SSC) tendon tear. The aim of this study was to investigate the long-term outcomes of this transfer in these patients. Methods. This was a retrospective study involving 30 patients with an irreparable SSC tear and those with a SSC tear combined with a reparable supraspinatus tear, who underwent a latissimus dorsi tendon transfer. Clinical scores and active range of motion (aROM), SSC-specific physical examination and the rate of return to work were assessed. Radiological assessment included recording the acromiohumeral distance (AHD), the Hamada grade of cuff tear arthropathy and the integrity of the transferred tendon. Statistical analysis compared preoperative, short-term (two years), and final follow-up at a mean of 8.7 years (7 to 10). Results. There were significant improvements in clinical scores, in the range and strength of internal rotation and aROM compared with the preoperative values in the 26 patients (87%) who were available for long-term follow-up. These improvements were maintained between short- and long-term follow-ups. Although there was a decreased mean AHD of 7.3 mm (SD 1.5) and an increased mean Hamada grade of 1.7 (SD 0.5) at final follow-up, the rate of progression of cuff tear arthropathy remained low-grade. Comparison between the isolated SSC and combined SSC and reparable supraspinatus tear groups showed no significant differences. At final follow-up, one patient (3.8%) had undergone revision surgery to a reverse shoulder arthroplasty (RSA). No neurological complications were associated with the procedure. Conclusion. Latissimus dorsi transfer for an irreparable SSC tendon tear resulted in a significant clinical improvement, particularly in pain, range and strength of internal rotation and aROM, which were maintained over a mean of 8.7 years following surgery. Given that this was a long-term outcome study, there was a low-grade progression in the rate of cuff tear arthropathy. Thus, the long-term clinical efficacy of latissimus dorsi tendon transfer in patients with irreparable SSC was confirmed as a joint-preserving procedure for these patients, suggesting it as an effective alternative to RSA in young, active patients without degenerative changes of the glenohumeral joint. Cite this article: Bone Joint J 2024;106-B(9):957–963

Latissimus dorsi anterior to major transfers have been advocated in the setting of loss of external rotation and elevation in conjunction with reverse shoulder replacement. Reverse shoulder replacement is a prosthesis specifically designed for shoulders with poor rotator cuff function. In the vast majority of cases, some teres minor function at the minimum is maintained in shoulders destined for a reverse shoulder replacement. However, in certain circumstances there is complete loss of any external rotation, and a muscle transfer can be performed in order to restore some external rotation function. A reverse shoulder replacement in the absence of any rotator cuff function goes into obligate internal rotation with elevation. A minimum of external rotation strength is necessary in order to maintain the arm in normal rotation. The first tip is patient selection. Physical examination of active external rotation, external rotation strength and forward elevation should be just performed. A latissimus transfer is indicated in patients who cannot maintain their arm in neutral to at least a few degrees of external rotation. A lag sign is another physical examination finding which can indicate complete loss of rotator cuff function. The latissimus dorsi transfer is performed by first identifying and releasing the latissimus from its insertion on the anterior humerus. The arthroplasty is performed. The passage for the latissimus muscle is developed carefully and being mindful of the axillary nerve in particular. The latissimus is directed inferior to the nerve and around the medial and posterior aspect of the proximal humerus. Different ways of securing the transfer to the humerus have been described including bone tunnels and anchors. Often it is easier to place the anchors and/or the bone tunnels prior to inserting the humeral prosthesis. The latissimus is secured in the new position, enabling it to participate in external rotation. The value of this is difficult to clearly establish. Most studies are evidence level IV and there are no good comparative studies in a controlled patient population. This is a good option for shoulders with no active external rotation, but they may increase overall complication rate. Complications include dislocation, infection, and transient nerve palsy

Aims

Since long-term outcome of teres major tendon transfer surgery for irreparable posterosuperior rotator cuff (RC) tears is largely unknown, the primary aim of this study was to evaluate the long-term outcome of the teres major transfer. We also aimed to report on the results of a cohort of patients with a similar indication for surgery that underwent a latissimus dorsi tendon transfer.

Introduction. This paper describes the kinetic and electromyographic contribution of principal muscles around the shoulder of a cohort of patients with reverse total shoulder arthroplasty (RTSA). Surgeries for RTSA significantly increased in the last five years. Initially developed to treat patients with cuff tear arthropathy and pseudoparalysis, wider indications for RTSA were described (massive non repairable rotator cuff tears, complex 4-parts fractures). Since Grammont's theory in 1985, the precise biomechanics of the RTSA has not yet been demonstrated in vivo. Clinical results of patients with RSTA are still unpredictable and vary one from another. Methods. We conducted an observational prospective cohort study comparing 9 patients with RTSA (surgery more than 6 months and rehabilitation process achieved) and 8 controls with normal shoulder function adjusted for age, sex and dominance. Assessment consisted in a synchronized analysis of range of motion (ROM) and muscular activity on electromyography (EMG) with the use of 7 bipolar cutaneous electrodes, 38 reflective markers and 8 motion-recording cameras. Electromyographic results were standardized and presented in muscular activity (RMS) adjusted with maximal isometric contractions according to the direction tested. Five basic movements were evaluated (flexion, abduction, neutral external rotation, external rotation in 90° of abduction and internal rotation in 90° of abduction). Student t-test were used for comparative descriptive analysis (p<0,05). Results. ROM is limited in the RSTA group (flexion 128,5 vs 152,6, p=0,04; abduction 150 vs 166, p=0,02; neutral ext rot 28.3 vs 75.6, p<0,01; 90° ext rot 26,43 vs 70,63, p<0,01, int rot 27.5 vs 49.4, p=0,01). Anterior and middle deltoid shows less muscular activation in RTSA than in controls, sustaining the deltoid potentiation described by Grammont. Posterior deltoid shows decreased activity in external rotation movements in RTSA. Upper trapezius is the main activator in all directions with an early and constant activity in RTSA (p<0,01). Latissimus dorsi demonstrates increased muscular activity in internal rotation with RTSA (p<0,01). Discussion. The sequence of muscular activation in RTSA is different than in normal shoulder. Grammont's theory is confirmed with this study. The significant contribution of both the trapezius and latissimus dorsi has never been described until today. New rehabilitation protocols targeted on those muscle groups could demonstrate better and more homogenous clinical results

Reverse total shoulder arthroplasty (RTSA) was designed to treat the cuff-deficient shoulder with arthritis and irreparable rotator cuff tears of the supraspinatus and infraspinatus tendons. The results of RTSA in this patient population have been very good and reliable in the majority of cases. However, it has also been reported that patients whose rotator cuff tear involves the supraspinatus, infraspinatus and teres minor and who demonstrate a ‘horn-blower's sign’ do very poorly if a muscle transfer is not performed to improve external rotation in these shoulders in abduction. The loss of the teres minor in these patients results in grave difficulty for the patient attempting to perform their activities of daily living even if they can obtain reasonable good forward flexion. The muscle transfer that is most commonly used for these select patients is a latissmus dorsi tendon transfer in conjunction with RTSA. The purpose of this talk is to review the pathology of this problem and review the technique for its surgical treatment.

Aims

Chronic osteomyelitis may recur if dead space management, after excision of infected bone, is inadequate. This study describes the results of a strategy for the management of deep bone infection and evaluates a new antibiotic-loaded biocomposite in the eradication of infection from bone defects.

We present the long-term results of open surgery for internal shoulder rotational deformity in brachial plexus birth palsy (BPBP).

From 1997 to 2005, 207 patients (107 females, 100 males, mean age 6.2 (0.6 to 34)) were operated on with subscapularis elongation and/or latissimus dorsi to infraspinatus transfer. Incongruent shoulder joints were relocated. The early results of these patients has been reported previously. We analysed 118 (64 females, 54 males, mean age 15.1 (7.6 to 34)) of the original patient cohort at a mean of 10.4 years (7.0 to 15.1) post-operatively. A third of patients with relocated joints had undergone secondary internal rotational osteotomy of the humerus.

A mixed effects models approach was used to evaluate the effects of surgery on shoulder rotation, abduction, and the Mallet score. Independent factors were time (pre-and post-surgery), gender, age, joint category (congruent, relocated, relocated plus osteotomy) and whether or not a transfer had been performed. Data from a previously published short-term evaluation were reworked in order to obtain pre-operative values.

The mean improvement in external rotation from pre-surgery to the long-term follow-up was 66.5° (95% confidence interval (CI) 61.5 to 71.6). The internal rotation had decreased by a mean of 22.6° (95% CI -18.7 to -26.5). The mean improvement in the three-grade aggregate Mallet score was 3.1 (95% CI 2.7 to 3.4), from 8.7 (95% CI 8.4 to 9.0) to 11.8 (11.5 to 12.1).

Our results show that open subscapularis elongation achieves good long-term results for patients with BPBP and an internal rotation contracture, providing lasting joint congruency and resolution of the trumpet sign, but with a moderate mean loss of internal rotation.

Cite this article: Bone Joint J 2014;96-B:1411–18

Introduction:

Reverse total shoulder arthroplasty (RTSA) has become an accepted surgical treatment for patients with severe deficiency of the rotator cuff. Despite the utility of RTSA in managing difficult shoulder problems, humeral rotation does not reliably improve and may even worsen following RTSA. Several approaches to increase active external rotation (aER) postoperatively have been proposed including the use of concomitant latissimus dorsi tendon transfer (LDTT) or the use of an increased lateral-offset glenosphere (LG). We hypothesized that clinical outcome and range of motion after RTSA with a +4 mm or +6 mm LG would be comparable to RTSA with LDTT in patients with a lack of aER preoperatively.

Background:

The purpose of this study was to compare the biomechanical effects of the trapezius transfer and the latissimus dorsi transfer in a cadaveric model of a massive posterosuperior rotator cuff tear.

Background:. Massive rotator cuff tear can cause functional disability due to instability and degenerative changes of the shoulder joint. In patients with massive irreparable rotator cuff tear, tendon transfer is often used as the salvage procedure. Latissimus dorsi and pectoris major transfer are technically demanding procedures and may incur complications. The biceps tendon transfer may provide a biologically superior tissue patch that improves the biomechanics of the shoulder joint in patients with irreparable rotator cuff tear. This study evaluated the functional outcomes of biceps tendon transfer for irreparable rotator cuff tear in 6 patients with two years and longer follow-up. Methods:. Between September 2006 and October 2011, 50 patients with 50 shoulders underwent surgical repair for MRI confirmed rotator cuff tear. Among them, six patients with massive irreparable rotator cuff tear were identified intraoperatively, and underwent proximal biceps tendon transfer to reconstruct the rotator cuff tear. The biceps tendon was tenodesed at the bicipital groove, and the proximal intra-articular portion of the biceps tendon was transected. The biceps graft was fanned out and the distal end fixed to the cancellous trough around the greater tuberosity with suture anchor. The anterior edge was sutured to the subscapularis and the posterior edge to the infraspinatus tendon or supraspinatus if present. Postoperative managements included sling protection and avoidance of strenuous exercises for 6 weeks, and then progressive rehabilitation until recovery. Results:. The evaluation parameters included VAS pain score, UCLA score, Constant score and AHES score, and X-rays of the shoulder. At follow-up of 25.3 ± 25.0 (range 22 to 63) months, the mean VAS pain score decreased from 9.3 ± 0.8 preoperatively to 1.7 ± 1.4 postoperatively (p < 0.001). All patients presented with significant improvements in pain and function of the shoulder for daily activities after surgery, however, only one patient achieved excellent results. There is no correlation of functional outcome with age, gender and body mass index. There was no infection or neurovascular complication. Discussion:. The biceps transfer provides soft tissue coverage of the humeral head, and restores the superior stability of the shoulder joint. The transferred biceps tendon also improves the mechanics and increases the compression force of the humeral head to the glenoid fossa. The results of the current study showed significant pain relief and improvement of shoulder function after biceps tendon transfer for irreparable rotator cuff tear. Conclusion:. Biceps tendon transfer is effective in the management of massive irreparable rotator cuff tear. The procedure is technically accessible with minimal surgical risks

In adults with brachial plexus injuries, lack of active external rotation at the shoulder is one of the most common residual deficits, significantly compromising upper limb function. There is a paucity of evidence to address this complex issue. We present our experience of isolated latissimus dorsi (LD) muscle transfer to achieve active external rotation. This is a retrospective review of 24 adult post-traumatic plexopathy patients who underwent isolated latissimus dorsi muscle transfer to restore external rotation of the shoulder between 1997 and 2010. All patients were male with a mean age of 34 years (21 to 57). All the patients underwent isolated LD muscle transfer using a standard technique to correct external rotational deficit. Outcome was assessed for improvement in active external rotation, arc of movement, muscle strength and return to work. The mean improvement in active external rotation from neutral was 24° (10° to 50°). The mean increase in arc of rotation was 52° (38° to 55°). Mean power of the external rotators was 3.5 Medical Research Council (MRC) grades (2 to 5).

A total of 21 patients (88%) were back in work by the time of last follow up. Of these, 13 had returned to their pre-injury occupation. Isolated latissimus dorsi muscle transfer provides a simple and reliable method of restoring useful active external rotation in adults with brachial plexus injuries with internal rotational deformity.

Cite this article: Bone Joint J 2013;95-B:660–3.

Latissimus dorsi tendon transfer (LDTT) is technically challenging. In order to clarify the local structural anatomy, we undertook a morphometric study using six complete cadavers (12 shoulders). Measurements were made from the tendon to the nearby neurovascular structures with the arm in two positions: flexed and internally rotated, and adducted in neutral rotation. The tendon was then transferred and measurements were taken from the edge of the tendon to a reference point on the humeral head in order to assess the effect of a novel two-stage release on the excursion of the tendon. With the shoulder flexed and internally rotated, the mean distances between the superior tendon edge and the radial nerve, brachial artery, axillary nerve and posterior circumflex artery were 30 mm (26 to 34), 28 mm (17 to 39), 21 mm (12 to 28) and 15 mm (10 to 21), respectively. The mean distance between the inferior tendon edge and the radial nerve, brachial artery and profunda brachii artery was 18 mm (8 to 27), 22 mm (15 to 32) and 14 mm (7 to 21), respectively. Moving the arm to a neutral position reduced these distances. A mean of 15 mm (8 to 21) was gained from a standard soft-tissue release, and 32 mm (20 to 45) from an extensile release. These figures help to define further the structural anatomy of this region and the potential for transfer of the latissimus dorsi tendon. Cite this article: Bone Joint J 2013;95-B:517–22

Introduction. In recently, Reverse shoulder arthroplasty (RSA) in patients with irreparable rotator cuff tear has been worldwidely performed. Many studies on RSA reported a good improvement in flexion of the sholulder, however, no improvement in external rotation (ER)and internal rotation motion (IR). Additionally, RSA has some risks to perform especially in younger patients, because high rates of complications such as deltoid stretching and loosening, infection, neurologic injury, dislocation, acromial fracture, and breakage of the prosthesis after long-term use were reported. Favard et al noted a 72% survival with a Constant-Murley score of <30 at 10 years with a marked break occurring at 8 years. Boileau et al noted caution is required, as such patients are often younger, and informed consent must obviously cover the high complication rate in this group, as well as the unknown longer-term outcome. Its use should be limited to elderly patients, arguably those aged over 70 years, with poor function and severe pain related to cuff deficiency. We developed a novel strategy in 2001, in which we used the humeral head to close the cuff defect and move the center of rotation medially and distally to increase the lever arm of the deltoid muscle. Aim. The aim of this study was to investigate clinical outcome of our strategy for younger patients with an irreparable rotator cuff tear. Materials and Methods. Eighteen shoulders (9 of male patients, 9 of female patients) of patients under 70 years old with an irreparable cuff tears and who were treated with Humeral Head Replacement (HHR) and cuff reconstruction were followed up for more than 12 months. The average age was 63.9 years (range, 58–69 years). The average follow-up period was 27.3 months (range, 12–76 months). The cuff defect was successfully closed in 8 shoulders, whereas 8 shoulders required a Latissimus Dorsi transfer; one other shoulder required a Pectralis Major transfer, and one required both Latissimus dorsi and pectoralis major transfers. Range of motion (flexion, ER), the shoulder score of Japanese Orthopaedic Association (JOA score), and complications were evaluated. Results. Shoulder pain decreased in all patients after surgery. JOA score was improved from 41.1 to 82.6 points after surgery, Flexion motion improved from 72.5 to 145.6 degrees postoperatively and ER increased from 17.5 to 37.8 degrees postoperatively. There were no complications. Conclusion. In our study, HHR using the small head of the humerus and cuff reconstruction for patients under 70 years old with an irreparable rotator cuff tear yielded favorable results as compared to RSA, especially in terms of the ER Furthermore, the advantages of our strategy is able to keep bone stock of the glenoid after surgery. If revision surgery is required, RSA can be performed. Since the patients included in our study were relatively active, long-term follow-up will be required to assess their progress

Introduction. Latissimus dorsi transfer is a procedure used in massive irreparable posterosuperior rotator cuff tears, in young patient with severe pain and significant functional impairment. The purpose of this retrospective study was to evaluate its clinical, radiological and electromyographic results. Methods. Forteen massive irreparable posterosuperior rotator cuff tears were performed with latissimus dorsi transfer between 2000 and 2008, and were reviewed at an average follow-up of 56 months and minimum of 19 months. Five transfers were primary reconstructions, and nine were revision surgeries. Patients’ mean age was 52.7 years. Clinical outcomes were measured by the Constant score, pain level, active range of motion, and strength. Osteoarthritis and acromiohumeral distance were measured on standardized radiographs. Ultrasound examination evaluate the integrity of the tendon. Axial images in CT-scan looked for muscle atrophy of latissimus dorsi in comparison with the controlateral. Electromyographic activity was measured during active flexion, abduction, adduction and rotations. Results. Twelve patients were satisfied. At the last follow-up, the average pain level according to a 100 mm visual analog scale was 31. The mean age and gender-matched Constant and Murley score improved from 34 to 60 % (p=0.003), forward elevation from 89° to 132° (p=0.006), abduction from 92° to 104°, external rotation from 12° to 24° (p=0.015). Mean abduction and external rotation strength were measured at 2.5 kg. Osteoarthritis progressed, and mean acromio-humeral distance has a significant decrease from 7.5 mm to 4.4 mm (p=0.003). Ultrasound examination showed twelve transferred tendons healed to the greater tuberosity. CT-scan showed a small atrophy of the transferred muscle, with a measurement of the cross-sectional area of the muscle belly at the inferior angle of the scapula at 1405 mm2, versus 1644 mm2 for the controlateral (p=0.06). Electromyographic analysis demonstrated a significant higher electric activity on the operative side during abduction and external rotation, and significant lower activity during adduction and internal rotation in comparison with the nonoperative side. Conclusions. Latissimus dorsi transfer allows for significant pain relief and function improvement in irreparable posterosuperior rotator cuff tears at young patients. Its electric activity increase in abduction and external rotation shows that the transferred muscle can integrate a new function and act like an active muscle transfer, in addition to an interposition or tenodesis effect. However we didn't find any depression of the humeral head or strength improvement

The current indications for functional restoration of extension of the knee following quadriceps resection or loss require reappraisal. The contribution of pedicled and free functional muscle transfer is likely to be over-emphasised in many studies, with good functional outcomes predominantly reported only in the context of cases with residual quadriceps function. In cases with total quadriceps resection or loss, all forms of reconstruction perform poorly. Furthermore, in smaller resections with loss of two or fewer components of the quadriceps, minimal impairment of function occurs in the absence of functional reconstruction, suggesting that functional restoration may not be warranted. Thus there is a paradox in the current approach to quadriceps reconstruction, in that small resections are likely to be over-treated and large resections remain under-treated.

This review suggests a shift is required in the approach and rationale for reconstructing functional extension of the knee after quadriceps resection or loss. A classification based on current evidence is suggested that emphasises more clearly the indications and rationale for functional transfers.

Massive, irreparable rotator cuff tears occur in about 15% of patients with ruptures of the rotator cuff tendons. There is no consistently agreed management for irreparable rotator cuff tears, however, latissimus dorsi tendon transfer is a recognised technique. We aimed to review the functional outcome of patients undergoing this operation at a single tertiary referral centre.

Fourteen latissimus dorsi transfer procedures in thirteen patients from May 2007 to May 2008 were retrospectively reviewed. The mean age of patients undergoing the procedure was fifty nine years. All patients were confirmed to have massive, irreparable (>5cm) rotator cuff tears as determined by MRI or ultrasound. Modified Constant scores (assessing shoulder pain, functional activity and movement) determined pre-operatively and post latissmus dorsi transfer were compared. The mean duration of follow up was 12 months.

The mean Modified Constant Score (maximum = 75) improved from 23 points pre-operaively to 52 points post latissimus dorsi transfer (p < 0.05). All patients had improvement in shoulder pain following the operation. There was a trend for younger patients to have greater improvement in functional activity and shoulder movement.

From our series, latissimus dorsi transfer is effective at improving functional outcomes in patients with massive, irreparable rotator cuff tears, especially in younger age groups.

Although reverse total shoulder arthroplasty (TSA) may restore shoulder abduction and forward flexion in the setting of a massive rotator cuff tear, the ability to use the extremity for ADL’s is often limited by external rotation weakness. Even though the reverse TSA restores abduction, the patient may be unable to bring the hand to his or her mouth because with the elbow flexed the weight of the hand causes the shoulder to fall into internal rotation. Concomitant transfer of latissimus dorsi (LDT) to the posterior greater tuberosity is a solution advocated by some surgeons. It is hypothesized that this inferiorly-directed force partially counteracts the superiorly-directed force of the deltoid, resulting in decreased shear forces on the glenoid baseplate-bone interface.

Three cadaver shoulder specimens were dissected and implanted with the reverse TSA. The rotator cuff was completely released to simulate a massive rotator cuff tear. Each shoulder was mounted in a shoulder controller that simulates neuromuscular control and replicates in vivo glenohumeral kinematics. The controller utilizes an optical, three dimensional tracking system. The humerus was weighted to simulate the full mass of the upper extremity and stepper motors were connected to the insertion points of the anterior, middle and posterior divisions of the deltoid by Spectra^® cord. Simulated active abduction in the scapular plane was performed using position closed-loop feedback control. The joint reaction force at the glenosphere was measured at 5° intervals from 30°–70°. A fourth stepper motor was then connected to the greater tuberosity with 2.73kg applied to simulate a LDT and the test was repeated. Five trials were performed under each condition. Four-factor ANOVA statistical analysis with Bonferroni correction and α = 0.05 was performed.

After simulated LDT the JRF demonstrated an increase in magnitude at abduction angles between 30° and 65° inclusive (p=0.033). The superiorly-directed shear force was significantly decreased as a result of the LDT between 45° and 70° (p< 0.0001). The compressive component of the JRF was increased for all abduction angles (p=0.025). The force required to achieve abduction increased for the middle deltoid (p=0.035) and anterior deltoid (p=0.036) for the simulated LDT condition at all abduction angles. The posterior deltoid force required for abduction decreased at all abduction angles (p=0.031).

In this model of reverse total shoulder arthroplasty concomitant transfer of latissimus dorsi decreased the superiorly-directed shear force. In addition to providing improved external rotation strength, these lower shear forces may have a protective effect on baseplate fixation by reducing the risk of failure in shear. This may provide additional justification for the transfer. Although superior shear was decreased, total JRF was increased as a result of an increase in the compressive component. Further investigation is needed to determine the potential gain in joint stability and whether the glenoid bone can support such elevated compressive forces. Additionally, the force required in the anterior and middle deltoid was increased after the LDT. This indicates the need for sufficient deltoid strength and rehabilitation.