Alkaptonuria with extensive ochronotic degeneration of the Achilles tendon and its surgical treatment: a case report and literature review

Abstract

Background Alkaptonuria is a rare genetic metabolic disorder due to deficiency of homogentisate 1,2-dioxygenase (HGD), an enzyme catalyzing the conversion of homogentisate to 4-maleylacetoacetate in the pathway for the catabolism of phenylalanine and tyrosine. HGD deficiency results in accumulation of homogentisic acid and its pigmented polymer. Ochronosis is a bluish-black discoloration due to the deposition of the polymer in collagenous tissues. Extensive ochronotic involvement of the Achilles tendon in alkaptonuria and its surgical treatment is rarely reported. Case report A 43-year-old man presented to our clinic in March 2019 with sudden onset of left Achilles tendon pain with no history of prior trauma. Surgical exploration revealed a complete disruption of the tendon at its attachment to the calcaneus. Black pigmentation was extensive and reached the calcaneal tuberosity, extending about 7 cm from the insertion. Discussion Achilles reconstruction was performed using flexor hallucis longus tendon transfer. The patient experienced uncomplicated healing with satisfactory functional results. Conclusion Orthopedic surgeons should be aware of the progressive nature of alkaptonuria. Extensive degenerative changes of the ruptured tendon should be suspected so that physicians can plan tendon repair and facilitate prompt surgical intervention.

Avulsive Achilles Tendon Rupture in a Patient With Alkaptonuria: A Case Report

“…Alkaptonuria patients are usually asymptomatic up to the fourth decade of life, and at this time, the manifestations of ochronotic osteoarthropathy begin to appear [ 2 , 6 ]. HGA accumulates in the connective tissue, causing irreversible damage to collagen [ 8 ].…”

“…Slower progress through the rehabilitation stages was ensured due to the increased risk of recurrence. In some situations, an augmentation with FHL is chosen [ 6 ]; however, in this patient, it was not possible since the FHL was chronically worn out. In cases of an increased gap, the procedure is not yet well defined.…”

“…In cases of an increased gap, the procedure is not yet well defined. However, Mwafi et al [ 6 ] proposed the following: if the patient has a gap of 1-2 cm, end-to-end repair with or without tenodesis augmentation is usually performed; if the gap is 2-5 cm, V-Y advancement with or without tenodesis augmentation is typically used; and finally, if the gap is greater than 5 cm, autograft or allograft tendon transfer or reconstruction is recommended. In this article, they also report that the FHL is the best tendon for reconstruction of the degenerated tendon for all defects greater than 2 cm.…”

“…Alkaptonuria was the first disease accepted to follow the classic Mendelian recessive inheritance, and Archibald Garrod was the physician who first described this condition in 1908 [ 5 ]. Its estimated prevalence is 1:250000 [ 6 ]. In this paper, we will report a case of Achilles rupture in a patient with a previous diagnosis of alkaptonuria.…”

Diş Renklenmeleri ve Güncel Tedavileri

“…Fenilketonüri doğuştan gelen metabolizma hatası, homojentisik asit oluşumunu teşvik eden tirozin ve fenilalanin metabolizmasının tamamlanamamasına sebep olur ve bu da dişlerde kahverengi bir renk değişikliğine neden olarak kalıcı dişleri etkiler (Mwafi N., Alasmar A, Al-Momani et.al., 2021). Tedaviye yanıt vermemektedirler.…”