Anatomical Total Shoulder Arthroplasty Despite Subscapularis Deficiency: A Case Report

Gabriele Cirigliano; Roland S. Camenzind; Mai Lan Dao Trong; Ulf Riede

Anatomical Total Shoulder Arthroplasty Despite Subscapularis Deficiency: A Case Report

Gabriele Cirigliano*, Roland S. Camenzind, Mai Lan Dao Trong, Ulf Riede

Department of Orthopedics and Traumatology, Bürgerspital Solothurn, Switzerland

*Corresponding author: Gabriele Cirigliano, Department of Orthopaedics and Traumatology,Bürgerspital Solothurn, Schöngrünstrasse 38, 4500 Solothurn, Switzerland. Tel: +41-326274601; Email: dr.gabrielecirigliano@gmail.com

Received Date: 14 April, 2020; Accepted Date: 01 May, 2020; Published Date: 06 May, 2020

Citation: Cirigliano G, Camenzind RS, Dao Trong ML, Riede U (2020) Anatomical Total Shoulder Arthroplasty Despite SubscapularisDeficiency: A Case Report. Ann Case Report 14: 372. DOI: 10.29011/2574-7754/100372

Abstract

Anatomical Total Shoulder Arthroplasty (TSA) for glenohumeral Osteoarthritis (OA) is usually reservedfor patients with a functional and intact rotator cuff. In contrast, little is known about TSA ininsufficient rotator cuff muscles. We report a case of a 50 years old male patient with painfulglenohumeral OA and Goutallier grade IV fatty infiltration of the Subscapularis (SSC) muscle, relatedto a previous open shoulder surgery over 20 years ago, treated with TSA. To our knowledge, this isthe only reported case of a patient with glenohumeral OA and a degenerated SSC muscle managedwith anatomical TSA. At two years’ follow-up he has a good clinical shoulder function, a stable joint and he is backto all previous activities.

Introduction

The presence of a functioning rotator cuff is a prerequisite to obtain a good result in anatomical Total ShoulderArthroplasty (TSA) [1]. In addition to proper component orientation, successful arthroplasty requiresaccurate restoration of soft tissue forces around the joint to maximize function. The Subscapularis(SSC) muscle plays a key role in shoulder biomechanics. It works as an internal rotator and depressesthe humeral head. In addition, it’s the anterior component of the glenohumeral force couple andprovides anterior shoulder stability [2]. In patients treated with anatomical TSA, postoperativelyoccurred SSC tendon tears lead to significant weakness in internal rotation strength as well as worse Disabilities of the Arm, Shoulder and Hand (DASH) scores [3]. Fatty degeneration of the subscapulariswas found to be a negative prognostic indicator in shoulder arthroplasty performed for primary osteoarthritis (OA)and exhibited a negative influence on the average postoperative scores (pain, mobility, strength, total Constant Score) [4].

Case Report

We report a case of a 50-years old labourer with a painful and debilitating secondary OA of the leftshoulder and a history of an unknown previous shoulder surgery more than 20 years ago.Conventional X-ray, Computed tomography (CT) and Magnetic Resonance Imaging (MRI) showed fatty infiltration of the SSC muscle Goutallier grade IV[5, 6], but full integrity of the scarred SSC tendon, withotherwise intact rotator cuff tendons(Figure 1-3). Active Range of Motion (ROM) was limited to abduction 90°,flexion 140°, external rotation 40°, and internal rotation until midthoracic spine. The Lift-off test andthe Belly-press test were positive, as well as the internal lag sign. The conservative therapy failed,and the pain persisted on a high level and was intolerable for the patient, therefore surgical treatment was required. Because of the young age of the patient, a anatomical TSA was planned and aSSC repair or augmentation with pectoralis major transfer was considered, depending onintraoperative findings.

Intraoperatively, the SSC showed a stable remodelled scar tissue, whichcorrectly inserted to the lesser tuberosity, so we decided against an additional pectoralis majortransfer (Figure 4). A stemless TSA (Affinis short, Mathys Ldt., Bettlach, Switzerland) was implantedthrough a lesser tuberosity osteotomy and transosseous refixation of the scarred SSC using #2 FiberWire(Arthrex, Naples, FL, USA)was performed.One and two years postoperatively, the patient was pain free and back at work, the active ROM was140° for flexion and abduction, 45° for external rotation and internal rotation was similar to thepreoperative finding until the midthoracic spine with a positive Lift-off and Belly-press test (Figure 5).Anterior apprehension sign could not be elicited in the clinical examination. X-rays showeda stable and centered TSA(Figure 6). Constant Score was 87, ASES Score 100 and subjective shoulder value was100%.

Discussion

SSC repair, healing, and integrity are described as essential features following TSA to achieve goodclinical results. It is known, that open surgeries using a SSC tenotomy may lead to atrophy and fattyinfiltration of the SSC muscle, resulting in postoperative SSC dysfunction [7]. SSC dysfunction should beaddressed depending on the cause. Primary repair of the ruptured SSC is performed if the tissue isamenable to repair [8, 9]. A pectoralis major or latissimus dorsi tendon transfer or reconstruction withAchilles tendon allograft or hamstring autograft may be used for augmentation of repairs in whichthe available tissue is inadequate for complete repair [10, 11]. Augmentation of a SSC deficiency can alsobe performed after initial implantation of an anatomical TSA and shows acceptable clinical results [10].

During surgery for TSA, SSC detachment is needed to visualize the humeral head and for optimalcomponent positioning.The best technique for SSC reattachment during TSA is currently stillcontroversial [12]. SSC tear after TSA and repair of the detached SSC seems to be more frequent thandiagnosed with physical exam [3]. Nevertheless, integrity of the SSC repair does not always correlatewith the clinical outcome.The results of our Case Report show that a high-grade fatty infiltration of the SSC in a young patientwith glenohumeral OA is not an absolute contraindication for TSA. Despite poor preoperativefunctional status and SSC muscle fatty infiltration good clinical shoulder function and stability can beachieved at two-years follow-up without the need of a muscle transfer or augmentation, dependingon the intraoperative findings. Certainly, the long-term course needs to be followed.

Figure 1: Pre-operative Anteroposterior (AP)- and scapular Y-radiographs of the left shoulder showing a high-grade glenohumeral osteoarthritis.

Figure 2: Axial Computed Tomography (CT) slice of the left shoulders at the level of the humeral head. Narrowing of the glenohumeral joint as well as fatty infiltration of the SSC muscle (black star) can be observed.

Figure 3: A) Axial slice of the preoperative Magnetic Resonance Imaging (MRI) of the left shoulders at the level of thehumeral head show again fatty infiltration of the SSC muscle (black star). B) Parasagittal view of allrotator cuff muscles shows again fatty infiltration of SSC muscle (black star) Goutallier grade IV.

Figure 4: Intraoperative view. The images show the SSC remodeled scar tissue (black arrows) afterthe lesser tuberosity (black star) osteotomy, before (A) and after (B) the transosseous refixation using #2 FiberWire® (Arthrex) (white arrows). In B, the sutures over the Button Plate Reinforcement (DePuy Synthes)fortransosseous fixations is shown (yellow arrow).

Figure 5: 2 years Follow-up: Flexion 140° (A), internal Rotation until the midthoracic spine(B), positive Belly-press Test (C).

Figure 6: 2 years post-operative AP, axial and scapular Y radiographs of the left shoulder show a well-centred glenohumeral joint.