Outcome and follow up:
The patient’s mobility improved well on physical therapy. After follow-up for two years, the patient’s condition was very good.
Discussion:Thumb hypoplasia is distinguished by extrinsic tendon dysplasia, thenar muscle hypoplasia, metacarpal adduction, and instability of the metacarpophalangeal (MCP) joint. In the most severe cases, thumb aplasia or MCP joint instability is present, and thumb removal surgery is advised as treatment. [5]
Thumb hypoplasia affects one in 100,000 live births. On the other side, 50% of these kids will also have a comparable impairment, however, the degree may vary. [6,7]
Both sexes are equally affected by the condition. [8,9]
Many classifications have graded congenital thumb hypoplasia and theses classifications aid in surgical decision-making. It was initially categorized by Müller, but Blauth’s classification (and BuckGramcko’s revision) is the one that is most frequently used today.  [10]
Blauth’s classification is based on different abnormalities of the bones, metacarpophalangeal (MCP) joint, carpometacarpal (CMC) joint and thenar muscles of the thumb. [8]
Clinical presentation ranges from minimal underdevelopment of the thumb (grade I) to a completely absent thumb (grade V) (table). [9]
Type 1 thumb hypoplasia in both hands is extremely rare, with an estimated incidence of less than 1 in a million births. The occurrence of type 1 hypoplasia in both hands and feet is even rarer, with only a few reported cases in the medical literature.
Congenital Hypoplastic thumb can be a part of the radial longitudinal deficiency spectrum or an isolated deformity. [11]
It can be also associated with syndromic manifestations such as Thrombocytopenia-absent radius syndrome, Holt-Oram syndrome, Fanconi syndrome and VACTERL sequences. Thus, a systematic evaluation of the musculoskeletal system, cardiovascular system, and complete blood count should be done for diagnosing such co-morbidities. The initial management involves identifying and managing associated extra-skeletal abnormalities for better outcomes. [6]