If youve recently developed pain and skin numbness just below the xiphoid process on the left side of your ribcageespecially when reaching or stretchingand are also experiencing a popping sensation, its important not to ignore these symptoms. From a physical therapy perspective, this presentation could be consistent with intercostal nerve irritation or a musculoskeletal condition such as costochondritis or slipping rib syndrome. These issues can create both localized pain and altered skin sensation, particularly if the rib or costal cartilage is inflamed or hypermobile. Given your history of cervical spine fusion, its also possible that compensatory changes in your thoracic spine or ribcage biomechanics are contributing to nerve irritation or muscle imbalance in the region. While its reassuring that youre not experiencing shortness of breath, chest tightness, or other cardiopulmonary symptoms, the persistence of these symptomsespecially the combination of pain, numbness, and mechanical poppingwarrants further evaluation. I strongly recommend consulting with your primary care physician or a physical medicine and rehabilitation PMR specialist. They may order imaging to rule out structural causes and guide you toward an appropriate physical therapy plan to address thoracic mobility, postural mechanics, and nerve sensitivity. Early intervention can help reduce symptoms, restore function, and prevent further irritation.