Myositis ossificans traumatica (circumscripta) and return to sport: A retrospective series of 19 cases

Painful and restricted hip due to myositis ossificans circumscripta of the pectineus muscle after pelvic fracture: A case report

RATIONALE

Myositis ossificans circumscripta (MOC) is a rare disorder that causes heterotopic bone formation in soft tissues. It usually occurs after trauma and affects large muscles of the extremities. MOC of the pectineus muscle is extremely rare and has not been reported to be treated surgically.

PATIENT CONCERNS

A 52-year-old woman presented with left hip pain and dysfunction 4 months after a traffic accident that caused pelvic and humeral fractures and cerebral hemorrhage.

DIAGNOSES

Radiological imaging revealed isolated ossification of the left pectineus muscle. The patient was diagnosed with MOC.

INTERVENTIONS

The patient underwent surgical resection of the ossified pectineus muscle followed by local radiation and medical therapy.

OUTCOMES

At 12 months postoperatively, she was asymptomatic and had normal hip function. No recurrence was observed on radiography.

LESSONS

MOC of the pectineus muscle is a rare condition that can cause severe hip dysfunction. Surgical resection combined with radiation and anti-inflammatory drugs can be an effective treatment option for patients who do not respond to conservative management.

Imaging of Muscle Injuries

Ultrasound (US) and MR imaging are the most common imaging modalities used to assess sports muscle injuries. The site of the muscle injury can be located at the peripheral aspect of the muscle (myofascial), within the muscle belly (musculotendinous), and with tendon involvement (intratendinous). Tears that affect the intramuscular tendon have a worse prognosis in terms of recovery time. US is an excellent method to evaluate muscle injuries, with high spatial and contrast resolution. MR imaging can be reserved for evaluation of professional athletes, surgical planning, differential diagnosis, and assessment of deep located and proximal muscle groups.

Case Report: Unable to Jump Like a Kangaroo Due to Myositis Ossificans Circumscripta

A male 10-year-old captive red kangaroo (Macropus rufus) was presented with a chronic progressive pelvic limb lameness and reluctance to jump. The general examination revealed a palpable induration of the lumbar epaxial muscles. Magnetic resonance imaging performed under general anesthesia revealed bilateral almost symmetric, well-circumscribed mass lesions in superficial erector spinae muscles. The lesions had irregular to multilobulated appearance with hyper-, hypo-, and isointense areas in T2- and T1-weighted (w) sequences without contrast enhancement. On computed tomography, a peripheral rim of mineralization was apparent. Histopathological analysis of a muscle biopsy showed osseous trabeculae with rare clusters of chondrocytes indicating metaplasia of muscle tissue to bone. No indications of inflammation or malignancy were visible. The clinical, histopathological, and imaging workup of this case was consistent with myositis ossificans circumscripta. This disorder is particularly well-known among human professional athletes such as basketball players, where excessive, chronic-repetitive force or blunt trauma causes microtrauma to the musculature. Metaplasia of muscle tissue due to abnormal regeneration processes causes heterotopic ossification. The kangaroo's clinical signs improved with cyto-reductive surgery, cage rest, weight reduction, and meloxicam without further relapse.

Fibro-Osseous Pseudotumor

Fibro-osseous pseudotumor is an extremely rare subcutaneous benign ossifying lesion associated with bone formation that is most commonly seen in the hands, followed by the toes. Because the tumor has a certain degree of invasiveness, it is often mistaken for malignancy, which leads to radical, excessive treatment. Our case involved a 32-year-old man with lesions on the left index finger. We documented the detailed data of diagnosis, treatment, and follow-up. We also conducted a review and summarized the published cases to advance our understanding of the disease, provide more accurate diagnostic criteria, and avoid inappropriate surgical procedures. [Orthopedics. 2021;44(6):e713-e718.].

Bilateral Post Traumatic Myositis Ossificans of Adductor Longus in a Young Soccer Player: A Case Report and Literature Review

ABSTRACT

Myositis ossificans traumatica (MOT) is a self-limiting and self-resolving pathology. In most cases, conservative treatment is chosen as the first step. Surgical treatment is reserved for cases of failure of conservative treatment with persistence of pain and mass. The case presented concerns an 18-year-old soccer player suffering from bilateral adductor longus (AL) MOT results following two different sports injuries. The patient reports the appearance of swelling and palpable mass at the proximal and medial region of the thigh, about 2 cm from the pubic symphysis, along the course of the adductor magnus. The radiological investigation showed the presence of a calcification along the course of the right and left AL muscles. Surgical treatment was considered for the right thigh injury, being symptomatic 1 year after the onset and refractory to other treatments. At 3 months of follow-up, the patient was asymptomatic and completed the rehabilitation program for the recovery of muscle strength and range of motion (ROM). In cases where MOT manifests with resistant pain, ROM restriction and daily activity reduction, surgical excision is the preferred option.

Epidemiology of Injuries in National Collegiate Athletic Association Men's Basketball: 2014-2015 Through 2018-2019

CONTEXT

Basketball has remained a popular sport for players and spectators in the United States since before the first National Collegiate Athletic Association men's championship tournament in 1939.

BACKGROUND

Routine examinations of men's basketball injuries are important for identifying emerging temporal patterns.

METHODS

Exposure and injury data collected in the National Collegiate Athletic Association Injury Surveillance Program during 2014-2015 through 2018-2019 athletic seasons were analyzed. Injury counts, rates, and proportions were used to describe injury characteristics, and injury rate ratios were used to examine differences in injury rates.

RESULTS

The overall injury rate was 7.28 per 1000 athlete exposures, with competition rates twice those of practices (injury rate ratio = 2.07; 95% CI = 1.93, 2.22). Injuries to the ankle (22.2%), knee (13.0%), head/face (11.3%), and hand/wrist (10.1%) accounted for most reported injuries, with sprains (30.4%), contusions (14.3%), and strains (13.9%) most commonly reported. Ankle sprain rates initially trended upward and decreased between 2017-2018 and 2018-2019; concussion rates remained relatively stable during 2014-2015 through 2018-2019.

CONCLUSIONS

Findings suggest that common injury rates are trending downward relative to previous study findings.

Pseudomalignant Myositis Ossificans of the Neck in a Child: Case Report and Review of the Literature

BACKGROUND

Myositis ossificans is a benign process of heterotopic bone formation developing in soft tissues that can mimic malignancy. Differential diagnosis can be difficult without a biopsy when it originates in atypical locations.

CASE DESCRIPTION

A 5½-year-old boy was admitted for a cervical tumor causing torticollis. The nodular tumor developed at the lateral border of the right C3-4 foramen, had calcification/ossification at its periphery, and was accompanied by a huge edematous reaction of the scalene muscles. The patient underwent an extensive work-up by pediatric oncologists. A biopsy was requested because of high suspicion of malignancy. At surgery, the lesion was benign on frozen sections and was completely resected, allowing the diagnosis of myositis ossificans. The patient made a rapid and complete recovery.

CONCLUSIONS

Myositis ossificans circumscripta is rare in children, especially in the neck region. The diagnostic challenge is to differentiate it from bone and soft tissue malignancies. Appropriate management, including surgery if needed, leads to an excellent outcome. Another concern is to exclude fibrodysplasia ossificans progressiva when atraumatic myositis ossificans develops in a young child in the neck or shoulder region.

Myositis Ossificans in Sport: A Review

Myositis ossificans is a benign, solitary, frequently self-limiting, ossifying soft-tissue mass encountered often in the active sporting population. Typically occurring within skeletal muscle - most often the brachialis, quadriceps and adductor muscle groups - lesions may arise with or without a traumatic history. The exact pathophysiology of these ossifying lesions is still poorly understood. Patients present with localized pain and swelling with loss of range of motion. Plain radiographs may not be able to detect early lesions, which allows for an expanded role of ultrasonography as an early screening modality, despite magnetic resonance imaging remaining the gold standard for imaging of soft tissue masses. Conservative treatment is implemented for most patients with excellent outcomes, with surgical excision being an option for persistent symptoms or progressive disease. Typically, athletes are able to progress to light activity at 2 to 3 months, full activity by 6 months, and back to their preinjury level by 1 year.

Soft tissue calcifications secondary to Hymenoptera stings: a potential prognostic CT imaging sign in pediatric patients

CONTEXT

Soft tissue calcifications (STCs) were incidentally found in some of the Hymenoptera-stung (HS) children when they underwent computed tomography (CT) scans for evaluating complications of vital organs. Afterwards, a predilection of STCs to the children with severe complications was clinically noticed. A hypothesis was then developed that STCs secondary to HS may correlate with poor outcomes.

OBJECTIVE

This study aims to firstly characterize the CT findings of STCs in HS children and to confirm our hypothesis that the occurrence of STCs may act as an indicator of poor outcomes in HS children.

MATERIALS AND METHODS

Children who received CT scanning after Hymenoptera sting from January 2011 to October 2016 in our hospital were analyzed retrospectively. Shape, location, and distribution of the STCs were described according to the CT findings. Then the enrolled cases were classified into Soft Tissue Calcification Group (STCG) and non-Soft tissue Calcification Group (non-STCG) to conduct prognostic comparisons of Sequential Organ Failure Assessment (SOFA) scores, incidence of main complications (acute liver failure (ALF), acute kidney injury stage III (AKI-III) and multiple organ failure (MOF)), length of hospital days, and in-hospital death, respectively. Pearson correlation was also utilized between the cumulative volume of STCs and the SOFA score.

RESULTS

Sixteen cases were enrolled, and STCs' incidence was 56.25% (9/16). Two STCG cases had diffuse nodular calcifications in their swollen subcutaneous tissue, and another seven had symmetrically stripy or patchy calcifications within or along local muscles. The SOFA scores during the first 3 days were all higher in STCG, and rose to the greatest difference at the third day (9.78 ± 2.17 vs. 2.29 ± 2.06, t = 7.009, p < .001); the incidence of ALF, AKI-III and MOF were significantly higher in STCG (66.67% vs. 0, p = .011), (77.78% vs. 0, p = .003) and (77.78% vs. 14.29%, p = .041); and children in STCG were treated with longer hospital durations (26.33 ± 8.41 days vs. 12.29 ± 7.36 days, t = 3.493, p = .004). One child in STCG died of cardiopulmonary failure, and no deaths occurred in non-STCG. No significant correlations presented between STCs cumulative volumes and SOFA score (r_Day1 = 0.096, p = .806; r_Day2 = 0.067, p = .863; r_Day3 = 0.024, p = .950).

CONCLUSION

Soft tissue calcifications detected on CT imaging following multiple Hymenoptera stings in pediatric patients may be a potential prognostic indicator of more severe complications and poorer outcomes.

Surgical excision of symptomatic mature posttraumatic myositis ossificans: characteristics and outcomes in 32 athletes

PURPOSE

The purpose of this study was to report characteristics and outcomes of surgical excision of symptomatic mature posttraumatic myositis ossificans in adult athletes. The hypothesis was that surgical excision of the ossified mass in these circumstances can effectively relief symptoms and result in return to high-level sports with minimal postoperative complications.

METHODS

All operations involving excision of posttraumatic heterotopic ossifications performed between 1987 and 2015 were reviewed. Included cases had isolated excision of posttraumatic myositis ossificans, whereas excluded cases had: (1) concomitant reattachment of tendon to bone; (2) chronic overuse injuries which preceded the development of the heterotopic mass or large calcifications which were excised from tendon-to-bone insertions; and (3) excision of heterotopic ossification from a ligament, capsule, or tendon insertion following avulsion injury without tendon-to-bone repair. After surgery, return to sports was allowed at 4-6 weeks.

RESULTS

Of 57 athletes undergoing excision of heterotopic ossifications, 32 were eligible as isolated excision of posttraumatic myositis ossificans. Twenty-four (75%) were ice hockey or soccer players. Median age was 23 years. Prior to surgery, patients were unable to continue their sports. At surgery, the ossification was excised from a thigh muscle in 27 (84%) cases. Median follow-up was 2 years (range 1-20 years). Outcome was Good/Excellent in 26 (81%) patients, corresponding to return to preinjury sports with minimal symptoms at sports activities. Preinjury Tegner activity level was resumed after surgery in 30 of 32 (94%) athletes, of whom 28 (94%) were involved in high-level sports corresponding to Tegner levels 8-10. No postoperative complications were recorded other than minimal insensitive areas at the periphery of skin incisions.

CONCLUSION

In high-level athletes who present chronic disabling mature posttraumatic myositis ossificans that interferes with their sports career, surgical excision of the heterotopic mass results in effective clinical improvement with return to sports and minimal postoperative risks.

LEVEL OF EVIDENCE

Case series, Level IV.

MR imaging and ultrasonography findings of early myositis ossificans: a case report

Myositis ossificans (MO) is a benign soft tissue lesion with non-neoplastic heterotopic bone formation. MO in the intermediate and mature stages can be easily diagnosed if characteristic imaging findings such as a peripheral zonal pattern of ossification with variable thickness is observed. However, it is difficult to correctly diagnose early MO because it can mimic malignancy clinically, radiologically, and histopathologically. We report a case of early pseudosarcomatous phase of non-traumatic MO with atypical imaging findings. A 59-year-old woman presented with pain followed by a mass in the left thigh within a week. MR imaging and ultrasonography showed an intramuscular lesion with preserved muscle fascicles in the vastus lateralis muscle. Intralesional ossification or calcification was not seen on ultrasonography. A diagnosis of myositis ossificans was made by ultrasonographically guided biopsy.