Orthopaedic Case of the Month:  A 16 year old Boy with a Recurrent Mass of the First Toe

SLR - September 2011 - Jennifer Gerteisen

Reference:  Prodinger PM, Pilge H, Prantl F, et al. 2011.  Orthopaedic Case of the Month:  A 16 year old Boy with a Recurrent Mass of the First Toe.  Clil Orthop Relat Res.  2011r469: 1216-1221.

Scientific Literature Review

Reviewed by:  Jennifer Gerteisen, DPM
Residency Program:  St John Hospital and Medical Center; Detroit, MI

Podiatric Relevance: 
This is a case report of an uncommon benign tumor which typically affects bones of the hands and feet.

Methods: 
16 year old male presented with a recurrent mass at the lateral base of the hallux which had initially developed following minor trauma in a soccer game six months prior.  A previous attempt at excision occurred 3 months after onset but the mass has redeveloped and was twice the initial size.   No constitutional symptoms or other pertinent past medical history was present.  Physical exam demonstrated a fixed, firm mass with well defined margins present at the lateral base of the hallux.   No evidence of infection or lymphadenopathy was present.  The MRI showed a heterogenous lesion which was indistinct at the adjacent phalanx cortex but did not demonstrate medullary involvement. 

Results: 
En bloc excision was performed during which the tumor and intact pseudocapsule were easily separated from the underlying bone.  Decortication was also performed at the underlying bone.  Grossly, the mass appeared like an osteochondroma with cartilage cap and a stalk of bony trabeculae.  Histologically, the bone characteristically stained blue with H&E and demonstrated other characteristics consistent with bizarre parosteal osteochondromatous proliferation (BPOP) with negative margins.  The patient continued to be free from recurrence ten months after resection.

Conclusions: 
BPOP typically has a history of trauma prior to generation of painless growing mass which affects the small bones of the hands and feet in addition to a tendency to recur.  Differential diagnoses on initial presentation should include benign (osteochondroma and surface chondroma), malignant parosteal osteosarcoma or reactive (Turret exostosis, florid reactive periostitis) lesions.   En bloc resection is the recommended treatment for symptomatic cases, with care to maintain the encompassing pseudocapsule and resect underlying periosteum and decorticate the underlying host bone.