Elsevier

Injury

Volume 40, Issue 11, November 2009, Pages 1167-1171
Injury

“Challenges in the management of fractures in osteopetrosis”! Review of literature and technical tips learned from long-term management of seven patients

https://doi.org/10.1016/j.injury.2009.02.009Get rights and content

Abstract

Osteopetrosis is a metabolic disorder with diminished bone resorption due to osteoclastic abnormality. It causes hard and brittle marble bone which fractures easily. Most of these fractures can be treated conservatively. Operative intervention when needed presents with unique technical challenges. While osteopetrotic hard bone may be penetrated with a drill bit; high friction and prolonged drilling can make the drill bit blunt. The heat generated can cause bone necrosis and break the drill bit. Besides this, brittleness of bones can cause intra-operative fractures. Due to the difficulties during the operation, the operative time may be prolonged thereby increasing the risk of post-operative infection. There is also a risk of delay in consolidation and non-union owning to impaired bone remodelling.

We present an account of seven patients treated for various fracture related problems occurring throughout their life due to this disease. Difficulties encountered during their treatment prompted us to present some general management principles.

Introduction

Osteopetrosis is a group of sclerosing bone dysplasia characterised by diminished osteoclast mediated skeletal resorption.13 First described by Albert Schonberg in 1904,1 approximately 300 cases have been reported in the literature. However, few reports aid in the management of these patients.

Osteopetrosis has been categorised clinically into three primary types (Table 1): infantile, or “malignant” osteopetrosis, inherited in an autosomal recessive inheritance pattern; “intermediate” autosomal recessive osteopetrosis; and autosomal dominant osteopetrosis.16, 3

The incidence of autosomal recessive osteopetrosis is approximately 1 in 300,000 births but is almost 10 times as high in Costa Rica.9 In severe forms of osteopetrosis, the insufficient bone marrow cavity cannot support adequate haematopoiesis. This results in extra-medullary haematopoiesis, which causes hepatosplenomegaly. Children who are severely affected can have cranial-nerve dysfunction, and visual deficits are often evident at birth or within the first few months of life.12, 10 Thrombocytopenia, anaemia, and infectious complications commonly cause death within the first decade. In less severe forms, patients have a normal life expectancy, but the brittle bone frequently fractures, particularly in autosomal dominant osteopetrosis.4

Recently gene mutations,19 carbonic anhydrase II dysfunction,20 chloride channel abnormality6 have been implicated in the causation of various types of osteopetrosis. However, many as yet have no identifiable abnormal gene. Classifications based on molecular events and associated physiology will undoubtedly be more precise. It is logical to expect that there is a role for haematopoietic stem-cell transplantation in patients with intrinsic osteoclast defects and severe osteopetrosis.18 Further investigations will facilitate correlation of the various genotypes with the clinical presentation, anticipated complications, prognosis, and expected response to treatment.18

Adult orthopaedic presentations in osteopetrosis include periodic back pain, bone pain, recurrent fractures especially in lower limbs, degenerative arthritis and infections.2 Other common problems are due to compression of cranial nerves leading to blindness, hearing and vision loss and facial nerve palsy.2

Fractures in osteopetrosis can occur at any age. Because the healing response is variable, management must be adapted and individualised to address the technical challenges unique to this patient population. Operative intervention has a high rate of intra-operative and post-operative complications.

Seven patients treated in Hartlepool and North Tees Hospital over the last 10 years were included in the study. All patients’ notes were reviewed retrospectively. Five of these were diagnosed as intermediate autosomal recessive and other two as adult onset autosomal dominant type of inheritance. They presented frequently to the hospital with multiple problem fractures.

An account of their fractures and other orthopaedic problems is detailed in Table 2.

Section snippets

Results

All the fracture in cases 3, 4 and 6 were treated conservatively. Most of the fractures in other cases healed with conservative treatment. The surgical procedures were undertaken in some specific fractures. Details of individual procedure, problems seen during these surgeries and the measures used to tackle the difficulties encountered are illustrated in Table 3 and Fig. 1, Fig. 2, Fig. 3, Fig. 4.

Discussion

Osteopetrosis is a disease which results into universal failure of the bone remodeling process. The osteoclasts are functionally abnormal. There is insufficient resorption leading to excessive accumulation of bone matrix; causing hard, dense bones with loss of medullary canal.14

Bone growth is also abnormal resulting in short and broad or long and thin brittle bones.7 Fractures are often transverse and may result from minor trauma.7

We can only find isolated reports of the management of fractures

Conclusions

For most long bone fractures non-operative treatment works well. However, surgical management is reasonable in certain circumstances such as fracture neck and shaft of femur, Coxa Vara and failure of conservative treatment. Surgery can be prolonged and difficult. Good preoperative planning should anticipate the forthcoming technical difficulties. The prolonged intra-operative and post-operative course and risk of infection should be included in the informed consent.

Conflict of interest

There are no identifiable illustrations in the article; it is not in conflict with any previously published material and does not affect the personal or financial interest of any one.

References (20)

  • R. Loria-Cortes et al.

    Osteopetrosis in children: a report of 26 cases

    J Pediatr

    (1977)
  • J.P. Strickland et al.

    Total joint arthroplasty in patients with osteopetrosis: a report of 5 cases and review of the literature

    J Arthroplasty

    (2005)
  • H.E. Albers-Schönberg

    Röntgenbilder einer seltenen Knockenerkrankung

    Munch Med Wochenschr

    (1904)
  • D.G. Armstrong et al.

    Orthopaedic management of osteopetrosis: results of a survey and review of the literature

    J Pediatr Orthop

    (1999)
  • Bhargava A., Blank R....
  • J. Bollerslev et al.

    Fracture patterns in two types of autosomal-dominant osteopetrosis

    Acta Orthop Scand

    (1989)
  • A. Chhabra et al.

    Management of proximal femoral shaft fractures in osteopetrosis: a case series using internal fixation

    Orthopedics

    (2005)
  • E. Cleiren et al.

    Albers-Schonberg disease (autosomal dominant osteopetrosis, type II) results from mutations in the ClCN7 chloride channel gene

    Hum Mol Genet

    (2001)
  • N. Dahl et al.

    Fracture patterns in malignant osteopetrosis (Albers-Schonberg disease)

    Arch Orthop Trauma Surg

    (1992)
  • L. De Palma et al.

    Fracture callus in osteopetrosis

    Clin Orthop Relat Res

    (1994)
There are more references available in the full text version of this article.

Cited by (0)

View full text