Posttraumatic Heterotopic Ossification of the Hip

Heterotopic ossification in right popliteal fossa causing arterial insufficiency

Heterotopic ossification (HO) is the abnormal formation of extra-skeletal bone in soft tissue, which can occur after trauma or surgery. HO in joints can cause pain, hinder mobility, and compress surrounding nerves and blood vessels. We present an unusual case of arterial insufficiency caused by HO in the right popliteal fossa.

Computer Navigation-Assisted Resection of Heterotopic Ossification Around the Hip: A Technical Note

Heterotopic ossification is a rare but debilitating situation. It occurs in patients who have undergone paralysis and/or immobilization. Hip osteoma is one of the most frequent locations and is associated with a significant functional handicap. Its treatment is based on surgical resection, which is a risky surgery that is not devoid of complications such as infections, hematoma, and recurrence. We describe in this paper a new surgical technique that adds to the classic hip osteoma resection: guidance with a navigation system coupled to a 3D imaging tool. We performed this technique on two patients (three hips, one bilateral case). We think that this technique makes the surgery safer with fewer complications.

Does Surgical Repair Benefit Pipkin Type I Femoral Head Fractures?: A Systematic Review and Meta-Analysis

Background: Femoral head fractures are rare injuries with or without traumatic dislocations. The management of these fractures is crucial to prevent the development of severe complications and to achieve optimal functional outcomes. Wide treatment options for Pipkin 1 femoral head fractures range from fragment excision, fixation following open reduction with internal fixation, or conservative treatment such as close reduction alone after fracture dislocation. However, the best decision making remains controversial not only due to lack of large trials, but also inconsistent results reported. Therefore, we aim to compare the operative with nonoperative outcomes of Pipkin type 1 patients. Patients and Methods: We systemically searched MEDLINE, EMBASE, Cochrane library, In-Process & Other Non-Indexed Citations to identify studies assessing outcomes of Pipkin type 1 patients after conservative treatment, and open reduction with excision or fixation. Data on comparison of clinical outcomes of each management were extracted including arthritis, heterotopic ossification (HO), avascular necrosis (AVN), and functional scores (Thompson Epstein, Merle' d Augine and Postel Score). We performed a meta-analysis with the available data. Results: Eight studies (7 case series and 1 RCT) were included in this study. In a pooled analysis, the overall rate of arthritis was 37% (95% CI, 2-79%), HO was 20% (95% CI, 2-45%), and AVN was 3% (95% CI, 0-16%). In comparison of management types, the excision group reached the best functional outcomes including Thompson Epstein Score (poor to worse, 9%; 95% CI, 0-27%) and Merle d' Aubigne and Postel Score (poor to worse, 18%; 95% CI, 3-38%); ORIF group had the highest AVN rate (11%; 95% CI, 0-92%); conservative treatment had the highest arthritis rate (67%; 95% CI: 0-100%) and lowest HO rate (2%; 95% CI, 0-28%). Discussion: This meta-analysis demonstrates that different procedures lead to various clinical outcomes: fragment excision may achieve better function, conservative treatment may result in a higher arthritis rate, while ORIFs may have a higher AVN rate. These findings may assist surgeons in tailoring their decision-making to specific patient profiles. Future RCTs with multicenter efforts are needed to validate associations found in this study. Level of Evidence: II, systematic review and meta-analysis.

Excision of Heterotopic Ossification around the Hip: Arthroscopic and Open Techniques

Heterotopic ossification (HO) can occur as a complication of various pathologies affecting the hip including trauma, tendon avulsions, chronic injury, spinal cord injury, and soft-tissue disruption caused by surgery. When HO is present alongside intra-articular hip pathology such as femoroacetabular impingement syndrome (FAIS) or labral pathology, consideration should be made to combine the surgical excision of the HO with the FAIS decompression or labral repair if the location and size of the HO is appropriate for arthroscopic excision. Often times, the HO is located in such a position that any central compartment work can be completed before turning to the HO excision. If an open approach is required, the modified Gibson approach can be used for lateral hip access, whereas the Smith-Petersen approach provides anterior hip access. In this Technical Note we discuss arthroscopic techniques for excision of HO in the setting of concomitant FAIS, with discussion of when HO excision occurs in relation to cam decompression and labral repair, and mention tips on how to approach HO excision through an open approach.

Pelvic MRI in spinal cord injury patients: incidence of muscle signal change and early heterotopic ossification

STUDY DESIGN

Prospective observational study.

OBJECTIVE

To evaluate pelvic MRI muscle signal changes and their association with early heterotopic ossification (HO) in patients with spinal cord injuries.

SETTING

National Spinal Injuries Unit, Stoke Mandeville, UK.

METHODS

Forty patients were imaged with at least two interval magnetic resonance (MR) studies of the pelvis in the first 6 months following a spinal cord injury. Scans were reviewed and scored for heterotopic ossification, muscle signal change and extent of muscle involvement.

RESULTS

Muscle signal change was present in 28 (70%) on the initial MRI and 31 (77%) by the second study. Six patients developed MR changes of prodromal or immature heterotopic ossification (15%). No restricted diffusion was demonstrated and no patient developed mature HO. Patients developing MR changes of early HO were more likely to have grade 3 muscle changes.

CONCLUSION

Increased T2 muscle signal is common following cord injury, is frequently progressive in the subacute period and is associated with complete injury and early MR signs of heterotopic ossification.

The role of preoperative vascular imaging and embolisation for the surgical resection of bilateral hip heterotopic ossification

The surgical excision of heterotopic ossification can provide improved function for patients; however, complications can include damage to nearby vessels and nerves, blood loss and recurrence. In the preoperative planning for excision, our case report describes the combination of CT angiography, preoperative embolisation of involved vascular structures and the use of intraoperative vascular surgery for dissection around key structures to aid in the reduction of morbidity in these patients.