Deltoid Contractures
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Introduction
Deltoid contracture is usually induced by repeated deep intramuscular injections, but may occasionally be due to congenital fibrosis. If severe, the characteristic manifestations of such contractures include winging, presence of a palpable cord inside the deltoid muscle, limitation of flexion and adduction of one glenoid-humeral joint, skin dimpling overlying the fibrous cords, rotation of the scapulae, as well as severe pain in the neck area and shoulder girdle. Nevertheless, the typical clinical presentations of deltoid contraction or the characteristic deformities of the shoulder may not be that apparent. Magnetic resonance imaging is extremely important in the diagnosis of deltoid contraction. It may show fibrotic cords inside this shoulder muscle, extending from the deltoid tuberosity to the superior acromial spine. Treatment should be conservative; surgical treatment for such contractures is only reserved for patients who suffer significant pain, deformities, and have failed to respond to an intensive rehabilitative program.
The literature in this topic consists of case reports as well as a few articles addressing extensive case series. Most of the case reports focus on the pathogenesis of deltoid contractures. Such contractures have been reported to occur in other areas such as the biceps, gluteus, triceps, and quadricep muscles. Fortunately, cases of occurrence of multiple contractures of muscle are extremely rare. Chen, Chou, and Huang (2010) studied a case with multiple muscle contractures of the bilateral gluteus, bilateral deltoid, as well as bilateral quadricep. All the patients had had repeated deep intramuscular injections when they were children and in adulthood. The researchers presented the radiographic features of abnormalities in the joint and bone, MRI (magnetic resonance imaging). The literature concluded that structural damage of body muscles due to injection intramuscularly is closely related to age of the patient, site of injection, as well as the chemical composition, volume, diffusion capacity, and pH of the injectate. The patient they studied had a deltoid muscular contracture that had been induced by intramuscular injection. According to Chen, Chou, and Huang (2010), the patient’s age, injection site, and medication do not matter.
Peter and Ven (2000), carried out a research aimed at determining the relative and absolute number of myofibrils in a contracting capsule of a joint over time. They compared this with non-operative control animals and the contralateral limb. The animals used were 18 white female rabbits of New Zealand origin. They were divided into groups: Group I (these were immobilized for 2 weeks), Group II (they were immobilized for 8 weeks), and Group III (they were immobilized for 8 weeks and then remobilized for 16 weeks). The model for the contraction comprised surgical trauma (the cruciate ligaments were excised and hyperextended) followed by immobilization of the knee with K-wire. The researchers did not manipulate the contralateral limb in anyway. No manipulation of either limb was made on the control animals. The group remobilized had the rabbits undergoing another surgical operation to extract the K-wire. The posterior knee capsule was removed then processed immunohistochemically to identify myofibroblasts. These were found in larger numbers in the limbs operated at 2 weeks, in comparison to the control limbs. Nevertheless, a significant reduction was observed in the limbs. The study aided in the understanding of the pathomechanism of contracture in a joint. They established that myofibroblasts will be expressed more highly in a contracture model, but the expression may be temporal. The implication is that myofibroblasts only become active early during contracture development. The importance of the findings lies in the understanding and development of strategies for treating patients with contractures, though the mechanism is largely unknown. More research is needed to determine how contractures in joints occur.
Jhunjhunwala (2005) studied the contracture of the deltoid muscle in children. According to Jhunjhunwala, the deltoid recovered completely without loss of abduction if treated promptly.
Shah (2003) investigated the causative factors of deltoid contracture. From his 5 case studies, he concluded that intramuscular injections could be the major cause of such contractures.
Ogawa (2001) studied the magnetic resonance imaging (MRI) features of a deltoid contracture. He compared the features with the histological characteristics of the bands before treatment. Most of the characteristics seen in the magnetic resonance image closely resembled those of the histological specimen after treatment.
Lian, Zhang, and Zhao (2010) investigated a case study where a contracture of the deltoid mimicked a shoulder dislocation. Their findings facilitated the identification of the misdiagnosis. However, it was not immediately apparent what the boy in question was suffering from until a clinical evaluation was done again.
From the foregoing, contracture of the deltoid is not adequately covered in the medical literature. The present research aimed at analyzing its etiopathogenesis and evaluating the outcome of treating the contracture surgically.
Questions from the interview included the following:
1. Can the patient achieve full motion of his or her shoulder joint after the operation?
2. Does the patient have any scar at the point of excision of the contracture bands?
3. Was the patient able to recover from the deformity that they presented with when they came to the hospital?
Methods
The participants were a group of 6 patients of American origin. Among the patients, four were females and two were males. The group had been derived from twenty patients who had suffered deltoid contractures, and had been operated in the period ranging from May 2001 to August 2013. Their enrolment to this retrospective study was voluntary, and informed consent was obtained beforehand. The patients fell in the 18 to 65 age group. It is worth mentioning that 2 of the patients were blood-related siblings.
In patients whose abduction deformity at the shoulder was more than 30°, surgery was the only medication. The cause of the contracture was not known in 3 of the patients (n = 3). In 2 of the patients, deltoid contracture had resulted from multiple injections in the deltoid muscle (n = 2). In the remaining patient, the contracture occurred following blunt trauma on the shoulder (n = 1). The condition had persisted for the duration of 6-11.5 years, which represented an average duration of 8.5 years. In 2 of the patients, there was bilateral contracture, and in 3 of them, the right side had a severe contracture. It can be said that the right side was affected predominantly. For all the patients, distal release, which involves an incision of the muscle close to its insertion, was employed as the therapeutic surgical operation. Each of these patients was followed up for average duration of 9 years and 6 months. This was equivalent to a range of 6 to 17 years. For evaluation, parameters such as persistence of deformity, pain, ability to use the arm, range of movements of the shoulder, as well as the muscle strength of the deltoid were used.
All the patients had a palpable fibrous band of contracture on the postero-lateral part of the deltoid muscle on palpation. Three of the patients had accessory fibrous bands that extended up to the anterolateral part of the deltoid muscle. One patient had a prominent furrow over the fibrous band. This helped to identify her easily. The patient had her humeral head in anterior subluxation.
All the 6 patients had come complaining of winging of the scapulae, which they considered a cosmetic deformity. When asked to attempt adducting their shoulder passively, the scapulas became extraordinarily prominent. In addition, all the patients complained of pain around the neck area, deltoid muscle itself, as well as the upper arm. However, no other deformity in the chest wall or spine was noted. Not all other body parts had any contractures. Shoulder skiagrams revealed a number of typical features that resembled clavicle tapering, as well as drooping of the acromial process. The latter covered the humeral greater tuberosity, causing maldevelopment of the joint. The patient whose contraction had persisted for over 10 years presented with humeral head subluxation.
The operative procedure was carried out on all patients. Having been anesthetized, each patient was put in the supine position with the affected shoulder lying on a folded sheet. In 3 patients, the surgeon approached the band by longitudinal incision. In the remaining 3 patients, a transverse incision was made over the fibrous band of the contracture. After identification of the band, it was separated from the mass of the muscle completely. Case 5 was the only one that did not undergo distal release; for him, humeral head subluxation required a proximal release. To prevent excessive bleeding, the transfixion stitches had to be placed over the ends of the palpable fibrous bands. Each band was later excised across the transfixion stitches. The purpose of the tissue excision was to obtain samples for histopathological processing. At times, it became necessary to cut apart some accessory bands. Such bands occurred within the postero-lateral segment of the muscle, and their identification was aided by adduction of the shoulder. Meticulous hemostasis was secured successfully. During the recovery period, the postoperative arm was strapped to the rest of the body. It was retained in adduction and internal rotation until the removal of the stitches. Only then, shoulder movements could be allowed provided the patient could perform such movements without experiencing a lot of pain.
Each patient was interviewed separately. He or she was required to appear before the doctor and answer questions, which the doctor read from a questionnaire. The questionnaire had been prepared beforehand. Some of the patients requested to fill the questionnaires instead of answering the questions orally. The request was granted, but the doctor remained within reach in case a patient encountered any difficulties in answering any of the questions due to medical terminologies. However, the questionnaire contained little jargon to enable the respondents to understand it and give accurate responses. The setting of the interview was a hospital room meant for continuous medical education sessions. This had been selected because it was the only area available during the day.
Results
After each patient was followed up individually for an average duration of 9.5 years, he or she achieved full correction of his or her deformity. They were assessed by asking to report whether there was pain on the shoulder, as well as the other parameters discussed previously. The results from the histopathological examination of excised tissue suggested features of prolonged inflammation with atrophied muscle tissue.
Among the resultant complications, 2 patients said they had developed keloids. The patients had been operated using the longitudinal incision. One patient said she had experienced painful limitation of motions of her shoulder joint whenever she tried to move it. The patient had her extensive contracture excised; subsequently he developed periscapulitis. The extensive excision was meant to correct the humeral head, which was in anterior subluxation. Another patient reported pain whose treatment was subacromion steroid injection. Another subject said he regained the full arc of motion of the shoulder joint, but complained the prominence on the vertebral border of his or her scapulas persisted. Two patients reported they did not attain full range of joint motion, and they could report pain whenever they tried to move the joint. The treatment complications reported included keloid (n = 2), painful restriction of joint motion (n = 1) and persistence prominence of the vertebral border of the scapulae (n = 3).
Discussion
The results incriminate not only intramuscular injections, but also genetic predisposition for deltoid contractures. In the current series of the deltoid muscle contractures, three cases did not report any history of deep intramuscular injections when they were children. In addition, the presence of shoulder deformity in the blood-related siblings who did not have a history of intramuscular injections can suggest there is a genetic predisposition (Banerji, 2008). The other siblings can be investigated, as well as other close relatives of the participants for further verification. However, such an inference needs to be validated using genetic studies.
In this series of cases, it was found that MFC (muscular fibrotic contracture) of the deltoid muscle was prevalent once a child attains the age of six years. Most Of the contractures (4) were segmental and full-thickness fibrous bands. They were usually anterolateral and infrequently postero-lateral (in 1 patient) in the muscle. Mostly contracture occurs on the right side (Jacobstein, 2010). All patients who had a history of deep intramuscular injections presented with laterally placed fibrous contracture bands. There were also accessory postero-lateral fibrous bands, along which the humeral head subluxated anteriorly (Wheeless, 2012). There lacked any anterior fibrous contracture band for any of the cases. Consequently, deep intramuscular injection can be considered the incriminating cause that results in serious deltoid contracture.
In the initial patient dealt with, a proximal release incision was utilized. This was done at the point where the deltoid muscle originates, with switching being connected to the distal incision that lay at the point of insertion. The study began with proximal incision in the first case, with careful attention not to pass the point of muscle origin. The study then switched over rapidly to the distal incision located close to the level of insertion of the muscle. It was established that in most of the patients, a large portion of the fibrous bands radiated principally from a point located distally close to the muscle insertion point. Therefore, the incision situated near the point of origin of the shoulder muscle was not seen as suitable for complete excision of all the contracture bands. Hence, a distal incision was preferred for the rest of the patients. To excise the main fibrous band totally, a distal incision done longitudinally was preferred. Three of patients with postero-lateral accessory contracture bands required a transverse incision done distally to facilitate the division of the primary band through one incision only, a technique adopted to avoid damaging the muscle extensively. Such extensive damage had resulted in formation of keloids in some patients.
In the series of the patient cases, results from histopathological examination of the excised muscle mass suggested features of prolonged inflammation, admixed with muscle cells and fibrous tissue. Nonetheless, all the cases gave satisfactory results with correction of the abduction shoulder deformity and winging scapulae. In one adult, however, the winging was not corrected until six months later. This can be partly attributed to the atrophy resulting from disuse of the serratus muscle. No abduction shoulder deformity or scapular winging recurred in any of the cases.
Several inferences can be drawn from this study. Deltoid contracture comes with the pathology of prolonged inflammation, and deep intramuscular injections into the deltoid muscle have been incriminated in the etiopathogenesis. To manage the condition effectively, distal release, where the deltoid muscle is released near its point of insertion, is recommended. In addition, excising the muscular fibrous contracture band distally with a longitudinal incision for the accessory postero-lateral band can relieve the contracture. For the combined bands, the incision needs to be done distally in the transverse section (Inokuchi, Naniwa, & Ogawa, 2000).