Anterior Heterotopic Ossification Research Articles

The Effect of Preoperative Cervical Spondylosis on Heterotopic Ossification After Cervical Disc Replacement.

Retrospective cohort study. This study aimed to explore the effect of preoperative cervical spondylosis on the heterotopic ossification (HO) formation in different locations after cervical disc replacement (CDR). The degree of preoperative cervical spondylosis was evaluated radiologically, including the intervertebral disc, uncovertebral joints, facet joints and ligaments. The effects of cervical spondylosis on the HO formation after CDR were analyzed according to the location of HO. Multivariate logistic regression was performed to identify the independent factors. 149 patients with a total of 196 arthroplasty segments were involved in this study. HO, anterior HO (AHO), and posterior HO (PHO) developed in 59.69%, 22.96%, and 41.84% levels, respectively. The significant factors in univariate analysis for PHO after CDR included the disc height loss, anterior osteophytes, preoperative uncovertebral joint osteophytes and facet joint degeneration. The incidence of adjacent segment degeneration (ASD) was significantly higher in the PHO group compared to that without PHO at the last follow-up (P = .003). The disc height loss in high-grade HO was significantly more than that in low-grade group (P = .039). Multivariate analysis identified disc height loss was the only independent factor for PHO (P = .009). No significant degenerative factors related to the formation of AHO were found. Preoperative cervical spondylosis predominantly affected the HO formation in the posterior disc space after CDR. The disc height loss was an independent risk factor for PHO formation. Rigorous criteria for the extent of preoperative disc height loss should be used when selecting appropriate candidates for CDR.

Ultrasound-guided Tenotomy and Osteectomy for the Treatment of Iliopsoas Impingement Post-total Hip Replacement

Ultrasound-guided Tenotomy and Osteectomy for the Treatment of Iliopsoas Impingement Post-total Hip Replacement

Association between anterior bone loss and anterior heterotopic ossification in hybrid surgery

BackgroundHybrid surgery (HS) has become an alternative procedure for the treatment of multilevel cervical degenerative disc disease with satisfactory outcomes. However, some adverse outcomes have recently emerged, such as heterotopic ossification (HO) and anterior bone loss (ABL). Furthermore, HO was found mostly located in the posterior and lateral of the cervical intervertebral disc space. The mechanism of anterior heterotopic ossification (AHO) formation may be different, and its relationship with ABL was uncertain.MethodsRadiographical and clinical outcomes of ninety-seven patients who had undergone contiguous two-level HS between December 2010 and December 2017 and with a minimum of 2-year follow-up were analyzed. Postoperative radiographs were evaluated and compared to the initial postoperative films to determine the incidence of ABL and AHO.ResultsThe overall incidence rate of ABL was 44.3% (43/97). It was identified in 70.6% of AHO cases (33.3% mild, 41.7% moderate, 25.0% severe) and 38.8% of non-AHO cases (38.7% mild, 45.2% moderate, 16.1% severe). A significant association between ABL and AHO occurrence was found (P = 0.016). There was no significant difference in prosthesis–endplate depth ratio or disc space angle change between the AHO group and the non-AHO group (P > 0.05). Compared with data preoperatively, clinical outcome scores significantly improved after surgery in both the AHO and non-AHO groups, with no significant differences between the two groups (P > 0.05).ConclusionABL was common in HS, and it related to AHO. The formation of AHO could be an integral part of postoperative bone remodeling, as well as ABL.

Is Anterior Bone Loss the Opposite of Anterior Heterotopic Ossification in Prestige-LP Cervical Disc Replacement?

Heterotopic ossification (HO) and anterior bone loss (ABL) are 2 complications in cervical disc replacement (CDR), which have impacts on the clinical outcomes. Physiologically, bone formation (HO) and bone loss are 2 sides of bone remodeling. However, clinically, some patients experienced anterior HO (AHO) after CDR, whereas other patients experienced ABL. Is there any factor in determining the fate of the vertebral bone in the anterior region? Is ABL the opposite of AHO? This study aims to answer these questions. Seventy patients with 1-level Prestige-LP CDR were retrospectively reviewed and were divided into an AHO group or ABL group. Radiologic outcomes, including cervical lordosis, sagittal vertical axis, functional spine unit angle, disc angle, range of motion, implant migration, subsidence, and adjacent segment degeneration were evaluated. Patient-reported clinical outcomes were also evaluated. AHO group showed significantly lower disc angle after surgery (0.9° ± 4.2°), compared with ABL group (6.7° ± 4.7°) (P < 0.001). The preoperative segmental range of motion was significantly higher in the AHO group (10.2° ± 3.3°) than in the ABL group (8.2° ± 3.7°) (P= 0.042). No correlation was observed between clinical outcomes and the presence of anterior bone remodeling. Both groups maintained cervical alignment and functional spine unit angle during long-term follow-up. No significant difference was found in the end plate preparation, implant subsidence, migration, or adjacent segment degeneration rate between the 2 groups. The differences in the disc angle showed the role of mechanical load in the anterior bone remodeling. Combined the results with the basic concepts of bone remodeling, ABL may be the opposite of AHO.

Anterior Heterotopic Ossification at the Talar Neck After Total Ankle Arthroplasty

Recently, as total ankle arthroplasty (TAA) has been widely performed, its outcomes and complications have been reported. Heterotopic ossification (HO) after TAA has been reported in the posterior compartment of the ankle. We report on a series of HOs that developed in the anterior compartment of the ankle at the talar neck region after TAA. TAA was performed using the Hintegra and the Mobility in 54 ankles (Hintegra, 21 ankles; Mobility, 33 ankles) from 2004 to 2012. The outcome was assessed by visual analog scale (VAS), the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, patient satisfaction, and radiographic evaluation. The HO was confirmed on the lateral ankle view. HO in the anterior compartment of the ankle was classified based on a modification of the Brooker classification. After TAA, 13 HOs developed in 12 of the 54 ankles. Six HOs developed in the anterior compartment, and 7 HOs developed in the posterior compartment. The majority of the anterior compartment HO (5/6) was observed in the Mobility group. There was no significant relationship between HO and the clinical outcomes (VAS score, P = .62; AOFAS score, P = .31; ankle range of motion, P = .31). Besides the posterior ankle, the anterior compartment of the ankle in the talar neck region was demonstrated to be another potential area for HO after TAA. The development of anterior HO was strongly related to the wide exposure of the cancellous bony surface at the talar neck and therefore occurred more often with the Mobility than with the Hintegra prosthesis. Level III, retrospective comparative case series.

Operative treatment of anterior heterotopic bone formation of the elbow in a patient with severe haemophilia A

There is no statistical data on the incidence of heterotopic ossification among patients with haemophilia, and a few reports documenting this entity in haemophilia are available. Although post-traumatic heterotopic ossification about the elbow is a well-recognized complication, we are not aware of any previously reported case in haemophiliacs. An 8-year-old boy with severe haemophilia A presented with fixed elbow in 80 degrees of flexion. Radiographs disclosed a mature anterior heterotopic ossification in the form of complete ulnohumeral bony bridge. Surgical excision of the heterotopic bone was performed. A full elbow range of motion was obtained after long-term physiotherapy. We conclude that this surgery is safe and successful in haemophilic patients, if performed at the right time under optimal situation.