Although not necessarily applicable to other forms of MD, steroids (i.e. deflazacort, prednisone) are showing promise for prolonging ambulatory ability and decreasing the rate of scoliosis [1–4]. Unfortunately, side effects such as obesity, osteopenia, and fractures may negate some of the positive attributes of the drugs [5–7]. Studies are ongoing to determine the appropriate dosing regimen and duration of steroid treatment as cessation of the drug seems to lead to rapid decline of muscle strength [1, 3].

A common presentation to the orthopaedic surgeon is for evaluation of toe walking in early childhood, often in the three- to five-year age range. Careful assessment of the child’s birth history and complete musculoskeletal physical exam is essential to rule out other causes such as idiopathic toe walking, cerebral palsy, etc. It is not uncommon for these children to have a mild equinus contracture at this age and physical therapy can aid in maintaining ankle joint range of motion. Serial casting may also be considered followed by maintenance of foot position with an ankle foot orthosis [8]. As the child continues to grow, hamstring and hip flexion contractures worsen as the proximal muscles weaken. Continued stretching and consideration of a knee-ankle-foot orthosis may be considered to prolong ambulation and standing ability [9–11]. Contractures also occur in the upper extremities and may require occupational therapy evaluation for stretching and assistive devices to aid in activities of daily living [12–14].

Patients not receiving steroids have a high incidence of developing scoliosis. Once confined to a wheelchair, thoracic supports may aid in maintaining sitting posture, but likely do not impact progression of the curve. Bracing is not indicated as the efficacy of brace treatment has not been shown to be beneficial in this condition [15–20].

Fractures are common once ambulatory ability is lost [5–7, 21]. Most fractures occur about the knee (most commonly the distal femur). Fracture management typically is non-operative. Care should be taken to avoid rigid immobilization with a heavy fiberglass or plaster cast as this can cause a fracture at the proximal end of the wrap. Most children are comfortable in a bulky wrap for four to six weeks until signs of radiographic union are evident. Bisphosphonates have been shown to improve back pain in patients with vertebral fractures, but have not been shown to decrease fracture risk [6].

When conservative measures fail, operative management of children with DMD can be beneficial. Clear goals of the surgical procedure must be discussed with and understood by the family. Shapiro et al. proposed a system of surgical approaches based on the ambulatory ability of the patient [9]. The three basic categories include ambulatory, rehabilitative, and palliative. The ambulatory category was subdivided into early-extensive, moderate, and minimum ambulatory approaches. The early-extensive approach is intended to be performed while the patient remains ambulatory and attempts to prevent the extensive contractures around the hip, knee, and ankle. The procedure involves excising the tensor fascia, lengthening the hip flexors, hamstrings, Achilles tendon, and possibly transferring the posterior tibialis through the inter-osseus membrane to the dorsum of the foot. While early reports of this method were promising, longer follow-up studies have failed to show much benefit. The “moderate ambulatory approach” is intended to address existing contractures in hopes to maintain ambulatory ability. The approach is similar to the extensive approach by utilizing intramuscular lengthening techniques of the gastrosoleus complex as well as lengthening the hamstrings. The lengthening of hip flexors and tensor fasciae showed no increased benefit. The minimum ambulatory approach addresses only the equinus contracture. An intramuscular approach such as the Vulpius lengthening is recommended to minimize the risk of over-lengthening potential that can occur with a z-lengthening. The rehabilitative approach is intended to allow a child with recent loss of ambulation to regain the ability to walk. This involves addressing the hip and knee contractures as well as percutaneously tenotomizing the Achilles. This approach requires post-operative brace management, but has been reported to increase ambulatory ability from several months to a few years. The palliative approach addresses the severe equinus deformity that prevents the patient from achieving a plantigrade foot to rest on the plate of his wheelchair. The procedure involves tenotomies of the Achilles, flexor digitorum, and flexor hallucis longus as well as tenotomy vs. transfer of the posterior tibialis to the dorsum of the foot [22, 23].

In the event the patient develops scoliosis, it should be addressed quickly (Cobb angle >20°) as it remains unclear which patients will progress [20, 24]. Bracing is ineffective in this condition. Delaying surgery may unintentionally cause the child to have to forego spinal fusion due to decline in pulmonary reserve [20, 24]. Surgical correction of scoliosis in patients with DMD has generated much debate. Instrumentation must be individualized to each patient and may include pedicle screw fixation, sublaminar wires, hooks, or a combination of anchors. Patients with pelvic obliquity should be fused to the pelvis, whereas those with a level pelvis may have success stopping at L5 [25–27]. The patient and family should be warned of potential risks such as bleeding, prolonged intubation, and infection. Additionally, children with moderate to severe upper extremity weakness may no longer be able to feed themselves as they lose the ability to move their trunk to their hands [28, 29].

As with Duchenne, corticosteroids play a role in the non-operative treatment of BMD. Johnsen [30] reported that two patients with Becker’s had a significant improvement in overall strength and reduction in serum creatine kinase levels after therapeutic treatment with prednisone. Because the severity of the disease varies with the level of functional dystrophin protein that is expressed, patients with BMD can differ in the clinical manifestations of the disease. Further studies are required in this patient population to determine which subset of patient’s with BMD would best benefit from prolonged corticosteroid treatment.

Patients with BMD often remain ambulatory longer and have an overall slower disease course than patients with DMD. Orthoses can be beneficial in patients who develop ankle and forefoot equinus [31]. Patients with BMD are felt to be better candidates for bracing than patients with Duchenne, both because they remain ambulatory and retain muscle strength longer.

Patients with BMD can develop similar orthopaedic conditions as those with Duchenne. However, the manifestations are typically delayed and less severe. The need for and timing of surgical intervention for orthopaedic manifestations of Becker’s is both reduced and delayed when compared with patients who have DMD [32].

Forefoot and ankle equinus have been described in these patients. When refractory to stretching and orthoses, intramuscular lengthening of the Achilles tendon is effective for management of ankle equinus [33]. Patients should also undergo concurrent posterior tibialis tendon transfer to the dorsum of the foot if appropriate [32, 33].

Scoliosis is seen more commonly in non-ambulatory adolescents. Because most patients with BMD remain ambulatory through adolescence and into adulthood, fewer patients develop scoliosis in adolescence [32]. Patients with BMD are still at greater risk for scolisosis overall and should be monitored closely with serial exams. As with patients who have DMD, patients with BMD should be considered surgical candidates when curves progress beyond 20° and the surgical principles are the same for both conditions [34].

Non-operative approaches to the management of FSHD have evolved over recent years. Early literature reported that muscle strengthening placed patients at risk for disease progression due to destruction of muscle fibers. However, more recent literature has shown that strength training and physical therapy can have positive effects. Andersen et al. showed that creatine kinase levels normalize within 24 h compared with pre-exercise levels, suggesting that irreversible or prolonged muscle damage is not an effect of exercise in these patients [35]. Olsen et al. found that a three-month low-intensity aerobic training program both improved oxygen uptake and caused no evidence of muscle damage among patients with FSHD [36]. Bakhtiary et al. attempted to optimize muscle function and found that simple motor learning programs could help FSHD patients adopt more effective muscle performance during basic tasks that require shoulder abduction and elbow flexion [37].

Taking things a step further, Pasotti et al. designed a six-month exercise and nutrition supplement program for a 43-year-old patient with FSHD [38]. At the time of the initiation of the program, the patient was noted to have severe proximal muscle weakness, hyperlordosis, and was no longer ambulatory. Pulmonary function tests revealed mild restrictive lung disease. The patient began a regimen of both endurance and strength training. Her diet was supplemented with branched chain amino acids, creatinine, and conjugated linoleic acid, based on previously published data that these agents can limit exercise-induced injury [39–41]. The patient developed a modest increase in shoulder abduction strength, with improvement in body mass composition and stabilization of pulmonary function tests, with no evidence of muscle soreness or muscle destruction [38].

There is also growing literature on the effects of albuterol as a potential adjunct in the treatment regimen for patients with facioscapulohumeral dystrophy. A pilot trial of 15 patients with FSHD shows that daily treatments of sustained-release albuterol over a three-month period significantly improved patients’ lean body mass and strength [42]. A follow-up randomized clinical trial involving 90 FSHD patients showed that daily treatment with long-acting albuterol resulted in improved grip strength and significantly improved muscle mass, although global measures of muscle strength did not significantly improve [43]. Albuterol was relatively well-tolerated by the patients in the study and the authors suggested that combining albuterol with other treatment modalities, such as strength training programs, might result in more significant anabolic effects.

Surgical management of facioscapulohumeral dystrophy is largely directed at scapular stabilization. The manifestation of FSHD that mostly limits daily activities is the patient’s inability to abduct his or her shoulders. Weakness of the trapezius, rhomboids, levator scapulae, and subscapularis causes significant scapular winging with any attempt at shoulder abduction. Stabilizing the scapula against the thoracic wall allows the deltoid and supraspinatus to abduct and forward flex the upper extremity. The shoulder range of motion achieved with stabilization is still less compared to that of unaffected patients, but the motion and strength is significantly improved post-operatively for patients with FSHD. Stabilization can be done either through scapulopexy or scapulothoracic arthrodesis.

Scapulopexy involves stabilizing the scapula against the thoracic cavity without attempting to achieve an arthrodesis. This can be achieved by using autograft, such as fascia lata graft, or other materials such as merseline tape, dacron, or looped wire [44, 45]. The procedure requires minimal post-operative immobilization. After surgery, patients can begin immediate shoulder range of motion. Because immediate range of motion is encouraged, patients can undergo contemporaneous bilateral scapulopexy or briefly stage the procedure so that both shoulders can be addressed. Ketenjian suggested that scapulopexy should be the preferred treatment in patients with FSHD because it does not interfere with rib excursion and therefore would not have significant negative effects on pulmonary function [45]. He reported improved shoulder abduction of an average 33°, as well as improvement in strength, endurance, pain, and cosmesis in five patients who underwent scapulopexy. Average patient follow-up in this study was 34 months. Giannini et al. reported significant improvements in both shoulder abduction and forward flexion in 10 patients who underwent scapulopexy for FSHD. The scapulae were fixed to the underlying fourth through seventh ribs using wires passed through bone tunnels. Although initial results were good, average forward flexion and muscle strength declined during long-term follow-up [44].

Scapulothoracic arthrodesis is a more technically demanding procedure than scapulopexy. The goal is to fuse the scapula to the underlying ribs. Numerous techniques have been described, although many follow a similar surgical plan [46–55]. Authors recommend making a posterior incision and elevating the rhomboids and trapezius off the medial border of the scapula, followed by a subperiosteal exposure of the underlying ribs [46, 48, 50, 55]. While most techniques recommend using iliac crest autograft, there are reports of successful arthrodesis using allograft [51]. Wires or multifilament cables are then threaded around the underlying ribs and attached to the scapula through bone tunnels, with more recently reported techniques recommending using a reconstruction or LCP plate to supplement scapular fixation and prevent scapular fracture and wire cut-out [47, 49, 54]. Most methods involve a post-operative immobilization period of 6–12 weeks to allow time for a successful fusion, although some authors encourage immediate range of motion post-operatively [50, 55]. Once shoulder range of motion is initiated, the rehabilitation protocol typically involves gentle range of motion passively, then actively, and then range of motion with weight bearing. The recovery time from this procedure is approximately six months. Simultaneous bilateral scapulothoracic arthrodesis is not encouraged because of the prolonged immobilization and weight-bearing restrictions post-operatively.

Both scapulopexy and scapulothoracic arthrodesis are complex procedures and a full pre-operative evaluation of the patient must be performed. Pre-operatively, the patient’s passive and active shoulder abduction and forward flexion should be evaluated and recorded. The patient’s active shoulder abduction and forward flexion should then be re-evaluated with the examiner stabilizing the patient’s scapula. This is known as the Horwitz maneuver. With the examiner holding the patient’s scapula, the deltoid and supraspinatus can contract against a stable scapula, allowing the muscles to abduct and forward flex the shoulder [33, 56]. Patients who will most benefit from a scapulopexy or scapulothoracic arthrodesis have active abduction and forward flexion from 90° to 120° when their scapulae are stabilized during the Horwitz maneuver. This represents the range of abduction required to carry out most activities of daily living [45]. Repeating the Horwitz maneuver with the scapula fixed at varying degrees of rotation against the thoracic wall can help determine the ideal position for scapular fixation intra-operatively by allowing the surgeon to see which scapula position gives the patient the optimal amount of shoulder motion.

When deciding between scapulopexy and scapulothoracic arthrodesis, the patient’s pulmonary function and rate of disease progression should both be considered. Scapulopexy is a less invasive procedure and has been shown to have a less significant effect on a patient’s pulmonary function, specifically forced vital capacity and overall vital capacity. This is even more important if the patient is considering bilateral procedures, as bilateral scapulothoracic arthrodesis has been shown to significantly affect pulmonary function both in the early recovery period and over the long-term follow-up. Also, patients with a rapidly progressive disease are likely better candidates for scapulopexy, as they would require less immobilization and would gain immediate function after the procedure. Most patients with FSHD have little to no decreased pulmonary function compared to unaffected patients and disease course is generally slow, with a normal life-expectancy [31–33, 56]. Therefore, most patients would have a greater overall benefit from a scapulothoracic arthrodesis as the range of motion and daily function is retained over time. Patients should be warned that both cross-body adduction and internal rotation behind the body will be limited post-operatively.

Intra-operatively, important considerations include how to position and prep the patient and where to anchor the scapula on the thoracic wall. Prepping and draping the entire upper extremity into the surgical field allows the surgeon to check pulses in the extremity to confirm that scapular stabilization has not affected the vascular supply to the upper extremity. Mackenzie et al. reported taking a patient back to the operating room for immediate revision after the patient was noted to have a cold upper extremity in the post-anesthesia recovery area [57]. Repositioning the scapula on the ribs resulted in immediate return of the radial pulse [57]. Including the extremity in the sterile field also allows the surgeon to range the arm after scapular stabilization to test the strength of the fixation. Most authors recommend attaching the scapula to the third through sixth or fourth through seventh ribs, in no more than 30° of external rotation. Preoperative evaluation can help the surgeon plan how to position the scapula on the thoracic wall to achieve optimal range of motion for the patient. Once the scapula is fixed to the ribs, it is recommended that the surgical field be filled with normal saline and that the anesthesia team initiate positive pressure ventilation to check for any leak in the pleura. If a leak is detected, a chest tube should be placed intra-operatively to prevent a pneumothorax post-operatively [49].