Poland syndrome occurs in approximately 1 in 20,000 to 1 in 30,000 live births. The condition affects males about 2-3 times more frequently than females. The right side of the body is affected approximately twice as often as the left side. The syndrome accounts for about 10-15% of congenital hand anomalies.

The exact cause of Poland syndrome remains uncertain, although the most widely accepted scenario is that it is the result of reduced blood flow to the developing chest wall and upper limbs during the 6th or 7th week of embryonic development. Most cases occur sporadically with no clear genetic inheritance pattern. Familial cases are rare, and no single causative gene mutation has been identified. Possible environmental influences such as through chemical or drug exposure have not been definitively found.

Symptoms of Poland syndrome vary widely in severity, from barely noticeable to significant physical deformities in the following areas:

• Chest wall and breast:  Absence or underdevelopment of the pectoralis major muscle (particularly in the region attached to the breastbone);  absent or underdeveloped breast tissue or nipple;  rib abnormalities and chest wall asymmetry;  absence of the pectoralis minor muscle. 

• Upper limb and hand:  Abnormally short, webbed fingers (syndactyly) on the affected side;  underdevelopment of the arm or forearm.

Other less common features:  Shoulder blade and backbone abnormalities;  heart, lung or kidney abnormalities;  limited subcutaneous fat and sparse armpit hair on the affected side.

Diagnosis is primarily clinical, based on a physical examination at birth (when hand abnormalities are present) or during puberty (when asymmetry becomes more obvious). Follow-up imaging may be done to assess muscle absence, soft tissue involvement and rib and bone abnormalities. Prenatal diagnosis via detailed fetal ultrasound is possible but not common. Genetic testing is not routinely indicated.

Treatment is individualized based on the severity of symptoms and functional impairment. It may include:

• Reconstructive surgery (often in adolescence or adulthood):

  • Chest wall reconstruction (muscle flaps, implants)

  • Breast reconstruction in females

  • Hand surgery for syndactyly or functional impairment

• Physical and occupational therapy: to optimize upper limb function

• Psychosocial support: particularly important for body image concerns

• Multidisciplinary care: involving plastic surgery, orthopedics, rehabilitation, and psychology as needed.

The prognosis for Poland syndrome is generally good. Most individuals with the condition lead normal, productive lives with few functional limitations. The psychological impact of visible bodily asymmetry can be significant, particularly during adolescence, but surgical reconstruction can help improve appearance and self-esteem.

Functional outcomes depend on the severity of involvement. Most people retain good function of the affected limb despite the muscle and hand anomalies. Athletic performance may be affected in severe cases, particularly activities requiring significant upper body strength on the affected side.

Life expectancy is normal, and the condition does not typically affect internal organ function unless rare associated cardiac or renal anomalies are present. With appropriate surgical intervention and support, cosmetic outcomes can be satisfactory.

1. Hashim EAA, Quek BH, Chandran S. 2021. “A narrative review of Poland's syndrome: theories of its genesis, evolution and its diagnosis and treatment.” Transl Pediatr. 10(4):1008-1019. doi: 10.21037/tp-20-320. PMID: 34012849; PMCID: PMC8107865.

2. Fokin AA, Robicsek F. 2002. “Poland’s syndrome revisited.” Ann Thorac Surg. 74(6): 2218–2225. doi: 10.1016/s0003-4975(02)04161-9. PMID: 12643435.

3. Urschel HC Jr. 2000. “Poland syndrome.” Chest Surg Clin N Am. 10(2):393–403. doi: 10.1053/j.semtcvs.2009.03.004. PMID: 19632568.

4. National Organization for Rare Disorders (NORD):  Poland syndrome.

5. Orphanet:  Poland syndrome.